« ПредыдущаяПродолжить »
a doubt could occur to the mind of any intelligent reader, re- the fossil teeth (from the Jurassic and Triassic formations) duced heights being invariably employed in the chapter in which known under the name of Ceratodus. the passage occurs, and in the book generally.
The interest attached to such a discovery will be easily The charge of inconsistency which the Reviewer urges with understood, if we review briefly the history of Lepidosiren, so much gusto, is based on the following passage in my Preface, and show the advance made by zoology in consequence at the beginning of Part I:“There is great danger in the present day lest science-teaching
of our acquaintance with this animal. should degenerate into the accumulation of disconnected facts and
The discovery is due to the well-known Austrian unex»lained formulæ, which burden the memory without culti- traveller, Natterer, who sent two examples from Villa vating the understanding, Prof. Deschanel has been eminently Nova on the Amazon River and the Rio Madeira to the successful in exhibiting facts in their mutual connection ; and his
Vienna Museum in the year 1837. Fitzinger, then Curator applications of algebra are always jud cious."
of the Collection of Reptiles, gave a somewhat superficial Which, the Reviewer thinks, justified the expectation that I description of it under the name of Lepidosiren paradoxa, would omit as many as possible of Deschanel's applications of referring it without hesitation to the class of Reptiles
. Algebra. It is not surprising that a writer accustomed to this Nearly at the same time a very similar animal was found style of inference should have an aversion to exact reasoning, and by Mr. Th. C. B. Weir, in Senegambia ; he presented should characterise the solution of problems by the application
two small examples to the Royal College of Surgeons ; of a little algebra as “intricate formulæ, which burden the
and Prof. Oven, then Curator of the Hunterian Museum, memory without cultivating the understanding."
I may remark, with reference to my former discussion with published a full description of them under the name of W. M.'W. in your pages, that the adoption of concrete units of Lepidosiren annectens, in the year 1839, explaining the mass, and derived units of force, has now received the official
reasons which induced him to regard this creature as a sanction of Sections A and G of the British Association, who
Fish. This view elicited further examination of the internal have appointed a committee to frame a system of no menclature structure of the American species by Profs. Bischoff and on this basis.
J. D. Everett Hyrtl, the former inclining to the opinion expressed by
Fitzinger, the latter conħrming, to the satisfaction of Newspaper Science
nearly all zoologists, the correctness of the conclusion KNOCKED up with work, I reluctantly followed the advice of arrived at by Owen. my medical man, and crossing the Channel so as to be more out Before the discovery of Lepiaosiren, zoologists distinof the way, resolved to eschew everything scientific for the next guished the class of Reptilia from that of Fishes by the few weeks at least, in order to recruit before the winter's labours
organ of respiration, the former being provided with commenced. Even here, however, I soon found that the desired
membranous lungs extending into the abdominal cavity, result was not so easily attainable as I had imagined, for the the latter breathing by gills only. Although the Batrachian first thing this morning, on entering the reading room of reptiles were known to breathe by external giils, as fishes, the bathing saloon, a French acquaintance, placing the Globe during the early stage of their metamorphosis, and although (of Monday evening, September 11) before me, directed my attention to its leading article on Prussian Artillery, adding of their life, yet the development of lungs in the adult
some of them retain those gills through the whole period significantly—"Viold, mon ami, a specimen of English scientific opinion !”
state and the co-existence of these organs with gills in the I must confess that it was not without a feeling of shame that | Perennibranchiates, were considered to be sufficient indicaI read an article, of which the following extracts will suffice to tions of their class-distinctness from fishes, among which give a correct idea.
no air-breathing organ was known. It is true Harvey and “Althrough the unchequered course of the late war was due to Hunter had pointed out that the air-bladder of the fish many causes, still it is now admitted on all sides that when the
was homologous with the lung of higher vertebrates; but Krupp guns were brought into the field the conclusion was prac. functionally it could not be compared to it, as it receives tically foregone.' “ The first public exhibition of what is now arterial blood like any other abdominal organ, returning known as the Krupp gun was the gigantic specimen of a breech
it in a deoxygenised condition. loading steel gun sent to our Exhibition of 1851. The steel of which this gun was made differs entirely from our Sheffield gun
Now Lepidoviren was found to be provided with gills, metal or from Bessemer metal, and is a composition invented by and a most perfect paired lung communicating by a ductus Krupp, and the result of a special process. The iron is alloyed
pneumaticus and glottis with the oesophagus, receiving with certain clays and also with a preparation of plumbago.
venous blood by strong arteries, and sending it back There are 100,000 'creusets' of this metal always in active em- directly to the heart in an oxygenised condition. Thereployment in the factory, and each 'creuset' contains from twenty fore, in this respect it did not differ from an Amphibian, to forty kilogrammes. The metal in a fluid state is poured into and dogmatical believers in the stability of our zoological large cy indrical moulds, where it remains for two hours till it
systems telt themselves quite justified in referring this has completely hardened. But the chief difficulties of the process creature to the Reptilians. lie in subjecting it to the steam hammer. For years the hammer
Nevertheless, the presence of certain other peculiariof greatest power in the factory had a force of 25,000 kilometres,"
ties of structure indicated rather an ichthyic than a rep&c. ! The italics are mine, and any one conversant with such sub
tilian affinity. The notochordal skeleton, and the apojects will perceive that no further comments are required. It
physes arranged as in many fishes, and not as in Amphionly remains for me to express my astonishment at seeing such
bians; the organ of hearing enclosed in the cartilaginous rubbish appear in the leading article of any newspaper of stand- capsule of the skull; the dentition extremely similar to ing, and I am sure your readers will agree with me that it is that of a Chimæra ; the intestinal tract traversed by a high time that journals specially devoted to science shoulı pro- spiral valve ; peritoneal outlets near the vent; no nasal test energetically against such representations being conveyed to canal to conduct air ; finally, the skin covered with scales, the public at home and abroad as expressions of English technical the fins supported by fin rays. All these are characters or scientific opinion.
not found in Batrachians, and connect Lepidosiren with Boulogne-sur-Mer, September 13
the class of Fishes ; but it was admitted that it makes
the nearest approach in that class to the Perennibranchiate THE NEW GANOID FISH (CERATODUS)
(CERATODUS) Amphibians. RECENTLY DISCOVERED IN QUEENSLAND
The question had next to be settled, what place in the
class of Fishes should be assigned to Lepidosiren; and as AL T the beginning of last year news reached Europe the view entertained by Joh. Müller is that adopted by the that a large Amphibian resembling Lípidosiren” majority of zoologists, we think it sufficient to refer to it
• had been discovered in Australia, and the curiosity of alone. Having determined that all Ganoid Fishes agree naturalists was still more excited when it was stated that with the Sharks and Rays in having an additional muscular this creature was provided with teeth extremely similar to division of the heart at the origin of the aorta, named bulbus
arteriosus, and provided with transverse series of valves air, and then descends again until the air is so much de. in its interior, he found that such a bulbus arteriosus was oxygenised as to render a renewal of it necessary. When likewise present in Lepidosiren, but with a very different we recollect that the animal evidently lives in mud or in valvular arrangement. This peculiarity, combined with water charged with the gases which are the product of the development of a lung, he considered to be sufficient decomposing organic matter, the usefulness or necessity to distinguish Lepidosiren as the type of a separate sub- of such an air-breathing apparatus, additional to the class, which he named Dipnoi, and placed at the head of gills, becomes at once apparent. Further we shall see the entire class.
that the limbs of this unwieldy and heavy animal are Thus, then, Lepidosiren was finally placed among the much too feeble and flexible to be of much use in locomoFishes; but from the time of its discovery dates the ten- tion on land ; they may assist it in its crawling, in water, dency of zoologists to subdivide the assemblage of cold. over the muddy bottom of a creek ; but the chief organ blooded animals not only where the development of a lung of locomotion is the compressed, broad, and flexible tail, ceases, but also where the development of gills begins. denoting by its shape and structure that the fish can exeOr, in other words, systematists became more and more cute rapid swimming motions. However, it is quite posconvinced that the old division of Reptiles and Fishes was sible that it is occasionally compelled to leave the water, insufficient, and that three classes of living cold blooded although I do not believe that it can exist without it in a Vertebrates should be distinguished, viz., Reptiles, Amphi- lively condition for any length of time. It is said to make bians, and Fishes, some regarding the second as even a grunting noise, which may be heard at night for some more closely allied to the third than to the first.
distance. This noise may be produced by the passage of When we find a group of animals represented by a very the air through the esophagus, when it is expelled for the small number of forms in the existing Fauna, we look to
purpose of renewal. Palæontology to fill up the seeming blanks; but Lepido- It deposits a great number of small eggs, which are imsiren did not appear to have any fossil representatives. pregnated after deposition. Nothing is known of their Prof. Owen stated (in 1839) that its teeth resembled "in development; but we may infer that the young are protheir paucity, relative size, and mode of fixation to the vided with external gills, like those of some other Ganoid maxillæ, those of the Chimera and some of the extinct Fishes. cartilaginous fishes, as Cochliodus and Ceratodus;” but The Barramunda (we will use the name given to it and no further inference was made from this fact as regards other similar fishes by the natives) is eel-shaped, but affinity. And.Prof. Huxley (in 1861), when drawing atten- considerably shorter and thicker than a common eel, and tion to analogous structures in Lepidosiren and certain covered with very large scales. The head is flattened and Devonian fishes, still maintained the entire absence of broad, the eye lateral and rather small, the mouth in front the Dipnoous type in the fossil state.
of the broad snout and moderately wide. The gill openThe discovery of a “gigantic Amphibian allied to the ings are a rather narrow slit on each side of the head. genus Lepido siren, from rivers in Queensland," and There are no external nostrils. The tail, which is of about named Ceratodus Forsteri by Mr. Krefft, promised to mark the same length as the body without the head, is comanother step in the advancement of our knowledge, and to pressed, and tapers to a point, but it is surrounded by a lend additional aid in determining the natural affinities of very broad fringe, supported by innumerable fine and these animals. As soon as Mr. Krefft had recognised the long fin-rays. There are two fore and two hind paddles, importance of this discovery, the trustees of the Australian similar to each other in shape and size, and very different Museum of Sydney took steps to secure well-preserved from the fins of ordinary fishes ; their central portion examples. They sent a collector into the district where being covered wita a scaly skin, and the entire paddle the animal was known to occur ; and, with their usual surrounded by a rayed fringe. If we were to cut off the liberality, they despatched to the British Museum, for hind part of the tail of a fish, the piece would bear a examination, the first specimens they could spare, by strong resemblance to one of the paired paddles. The which I was enabled to present a full account of its vent is situated in the median line of the abdomen organisation to the Royal Society. It is not my intention between the paddles. to enter here into the details of the results of this examina- In order to obtain a view of the inside of the mouth, tion ; I must be satisfied with giving a short description it is necessary to slit it open, at least on one side. We of it, pointing out some of the bearings which this dis- then notice that there are a pair of nasal openings within covery has upon the advancement of science.
and on each side of the cavity of the mouth. The palate The fish (for this it proved to be, and even more so than is armed with a pair of large, long, dental plates, with a Lepidosiren) appears to be not uncommon in some dis- Aattish, undulated, and punctated surface, and with five tricts of Queensland ; specimens have been obtained from or six sharp prongs on the outer side, entirely similar to the Burnett, Dawson, and Mary rivers, some high up in the fossil teeth described under the name of Ceratodus. persectly fresh water, others descending into the lower Two similar dental plates of the lower jaw correspond to brackish portions. It is said to grow to a length of six the upper, their undulated surface fitting exacıly to that feet, the largest example sent to the British Museum being of the opposite teeth. Beside these molars the front part about three and a half feet long. The flesh is excellent of the upper jaw (vomer) is armed with two obliquely eating, and of salmon colour, hence it is called by the placed incisor-like dental lamellæ, which have no corresquatters Burnett or Dawson salmon. Its food consists sponding teeth in the lower jaw. As we know the kind of the decaying leaves of myrtaceous and other plants, of food taken by the Barramunda, the use of their teeth with which the stomach and intestine are crammed. is apparent. The incisors will assist in taking up, or even Probably now and then it swallows, perhaps accidentally, tearing off, leaves, which are then partially crushed besome aquatic animal ; but it is rather doubtful whether it tween the undulated surfaces of the molars. can be caught by using living animals as bait. It is also The skeleton consists of a cartilaginous basis, in the stated that it is in the habit of going on land, or at least form of a long tapering chord for the body and tail, and on mud-flats; and this assertion appears to be borne out in that of a capsule for the head. No segmentation into by the fact that it is provided with a true lung: On the separate vertebræ is visible in any part of the notochord other hand, we must recollect that a similar belief was but it supports a considerable number of apophyses, the entertained with regard to Lepidosiren, of which now abdominal of which bear well developed ribs, all being numerous examples have been kept in captivity, but none solid cartilaginous rods, with a thin sheath of bone. In have shown a tendency to leave the water. I think it the same manner no part of the brain-capsule is ossified, much more probable that this animal rises now and then but it is nearly entirely enclosed in thin bony lamellæ. to the surface of the water, in order to fill its lungs with This is also the structure of the appendages of the skull,
as the mandible and the hyoid and scapulary arches.
Instead of the two longitudinal valves of the From a study of the skull, it becomes apparent at once Dipnoous heart, the bulbus arteriosus is provided with two why in fossil teeth of Ceratodus nothing or very little of or three transverse series, of which one only is fully devethe bone attached to them has been preserved. Those loped; or, in other words, Ceratodus proved to be a Ganoid teeth rest on cartilage as well as on bone, the latter being fish. But, as Cerat"dus and Lepidosiren are in all other a very thin and porous layer which could not be preserved, points too closely allied to be separated in two distinct unless the progress of stratification had been going on sub-classes or even sub-orders, we must arrive at the con. with as little disturbance as in the Solenhofen Schiefers ; clusion to drop the Dipnoi as a sub-class, and to refer but the matrix in which fossil Ceratodont teeth are found Lepidosiren also to the Ganoids, which will then be characshows that it was formed under very different conditions, terised, not by transverse series of valves, but by the and it is certainly not of a nature to permit the supposition presence of a muscular, contractile bulbus arteriosus with that thin porous lamellæ of bone would have been pre- valves, transverse or longitudinal, in its interior, a strucserved entire.
ture which they have in common with the sharks and rays The structure of the skeleton reminds us much of that (Plagiostomatn). of the sturgeons, Chimæra, and especially of Lepidosiren; The intestinal tract is a large straight sac with an and of all the modifications by which it differs from these internal spiral valve, as in the Ganoids and Plagiostomes. types, perhaps none is of greater interest than that ob- The kidneys are paired, the ureters enter a very small served in the paddles. The central part of the paddle, urine bladder or cloaca at the back of, and partly confluent which we have found externally to be covered with scales, with, the rectum. is supported by a jointed axis of cartilage extending The organs of propagation show some noteworthy from the root to the extremity of the paddle ; each joint peculiarities. They are paired, in long bands. The male bears a pair of three- or two- or one-jointed branches. organs have no visible outlet, although a seminiserous duct This is the case in the hind as well as fore paddles, and has been found traversing the substance of the testicle we are justified in supposing that those extinct Ganoids of through nearly its whole length ; no outward opening could which impressions of paddles with scaly centres have been be discovered, and it is not known how the semen preserved, were provided with a similar internal skeleton. is discharged. The ova are small, very numerous, and Professor Huxley, some years ago, drew attention to attached to transverse laminæ of the ovaries; when the analogy existing between the filamentary limbs of mature, they fall into the abdominal cavity, as in the Lepidosiren and the lobate fins of certain extinct Ganoids, salmon tribe, and would appear to be expelled through and the correctness of this view is fully borne out by the two wide slits behind the vent. Yet each ovary is accomdiscovery of Ceratodus, inasmuch as the Lepidosiren-limb panied by a long oviduct, as in the sturgeon or Lepidoproves to be typically the same as that of Ceratodus, but siren, though it probably has no function, and is only reduced to the jointed central axis.
indicative of an approximation of this remarkable fish to The gills are perfectly developed, four on each side. higher types. Such are some of the principle features of They are broad lamellated membranes, free from each the organisation of the Barramunda ; and it remains now other, but attached to the outer walls of the gill-cavity. to add some remarks on its affinities and its place in the One can hardly doubt that, in water of normal composi- system.
A. GÜNTHER tion, they are sufficient for the purpose of breathing. A
(To be continued.) lung, however, is superadded to them, a true lung, which receives blood from a branch of the aorta, and returns it directly to the heart by a separate vein. Whilst the ON EXOGENOUS STRUCTURES AMONGST Barramunda is in water sufficiently pure to yield the ne- THE STEMS OF THE COAL-MEASURES cessary supply of oxygen, the function of breathing rests with the gills alone, and the lung receives arterial blood,
IN N a memoir recently read before the Royal Society, I returning venous blood, like all the other organs of the propounded a new classification of the vascular crypbody ; under this condition it does not differ from the togams, and at the late meeting of the British Association air-bladder of other fishes. But when the fish is com- at Edinburgh I brought the same subject forward, when pelled to sojourn in thick muddy water, charged with my views were opposed by Mr. Carruthers, Dr. M‘Nab, noxious gases, which must be the case very frequently and Prof. Dyer, as reported in the columns of NATURE during the droughts which annually exhaust the creeks of for Aug. 31. I was well aware that when I disturbed tropical Australia, it commences to breathe air in the way existing and time-honoured systems of classification I indicated above ; under this condition the pulmonary vein should meet with such opposition ; but, being thoroughly carries purely arterial blood to the heart, where it is convinced that my views are sound, and that they will mixed with venous blood and distributed to the various ultimately be adopted, it only remains for me to face the organs of the body. If the medium in which the fish conflict, and persevere with my demonstrations of what I happens to be is perfectly unfit for breathing, the gills believe to be true. My present object is to do what was cease to have any function ; if only in a less degree, the impossible in the hurried and unsatisfactory discussions gills may still continue to assist in respiration. In short, that frequently arose at the meetings of the British Assothe organisation of the Barramunda is such as to justify ciation to accomplish, viz. : to take care that there shall us in the assertion that it can breathe by either gills or be no misunderstanding as to the real points at issue. lung alone, or by both simultaneously.
My opponents seek to interpret the gigantic arborescent With regard to the structure of the lung, it shows a stems of the coal-measures by the light of the dwarsed nearer approach to the air-bladder of other living Ganoid and degraded examples of vascular cryptogams which fishes than that of Lepidosiren ; it is not prired, but con- constitute their living representatives. 1, on the other sists of a single long sac extending nearly to the end of hand, claim to interpret the latter by the former, some of the abdominal cavity. Yet the interior of the sac shows which, the Lycopods, for example, instead of being feeble a symmetrical arrangement of the right and left side, being things trailing in the grass, had stems three feet in diamesubdivided into numerous cellular compartments, by which ter, and rising a hundred feet into the air Instead of the respiratory surface is much increased in extent.
merely constituting a verdant carpet for forests of noble The next organ of importance for determining the exogens and endogens, they were the forest; here, consystematic affinities of the Barramunda is the heart. sequently, we might expect that whatever characteristic Considering the great resemblance this fish has shown in features they po sessed would be developed and displayed other respects to Lepidosiren, I fully expected to find this in their utmost perfection. organ agree also with the Dipnoous type ; but this is not Mr. Carruthers' fundamental argument is, that I, in my classification, elevate the vegetative organs at the cost of facts do not sustain him. The huge lepidodendroid carthe reproductive ones. I reply I am merely applying prin. boniferous plants give it a direct contradiction. They ciples already adopted by botanists throughout the world. have not closed vascular bundles, and their growth did
, They are those of DeCandolle, of Endlicher, of Lindley, not cease after a limited time, but was obviously conof Brongniart, and of Balfour. These writers, in common tinued, being sustained by a cambium layer, until the with most others, recognise primary distinctions that are plants assumed the magnificent dimensions which their purely vegetative. Not only are those which separate fossil remains now exhibit. That the large vascular vascular from cellular plants of this character, but the cylinder of the fossil forms is a development of what is further ones of exogens, endogens, acrogens, and thallo- seen, not only in l.ycopodium chamæcyparinus referred gens are of the same nature. The fact of the closest to by Dr. M'Nab, but in every one of the numerous resemblance of the inflorescence, and of the formation of Lycopods of which I have examined sections, I have never the embryo in the embryo-sac in the two groups, does not denied. Quite the contrary. But I repeat we must interprevent the separation of the flowering plants into exogens pret the significance of the least developed form by that and endogens. Turning from the phanerogamous to the which is most developed. Consequently we must regard cryptogamic plants, we find that nearly every writer of the irregular vascular bundles which exist, commingled importance adopts vegetative features as the basis of his with cellular tissues, in the axis of each living Lycopod, classification. DeCandolle divides his Acrogens into those as a degraded wood cylinder, whose nature can only be which have and those which have not vascular tissues. understood by reference to what it once was when its Endlicher's primary term Cormaphyla refers to a vegetative parent tree was one of the glories of the primæval forest. feature, viz., the possession of a stem, whilst his secondary The race as a whole has become degenerate, and the stem divisions of Acrobrya, Amphibrya, and Acramphibrya aí being no longer called upon to sustain a losty superstrucrefer to the mode of growth and not to fructification. ture, its structure has become equally degenerate. Lindley again distinguishes his flowerless plants according I will not enter in detail into the question of the nomenas they are acrogens or thallogens ; whilst Balsour cha. clature of the various parts of these exogenous cryptoracterises them primarily as acrogens or cormogens and gamic stems, but reserve that subject for some other thallogens. In thus dwelling upon the vegetative element occasion, after my detailed memoirs now in the hands of the cryptogams, I am merely treading in the steps of of the Royal Society have been published. I will merely nearly every writer of note who has written on these subo | express my conviction that Mr. Carruthers, who differs jects. So much, therefore, for the primary point. widely from me on the subject, assumes the very question In many
of the discussions which have taken place, my in debate between us. opponents have made the mistake of supposing that I was He holds that we can draw no parallel between the contrying to prove these fossil coal-plants to be dicotyledonous ditions existing in the stems of Cryptogams and those of exogens. Whereas what I have throughout contended for Phanerogams. This is precisely what I contend we can is that they are true cryptogams with an exogenous woody do, and I trust to be able, as my self-appointed task proaxis. Mr. Carruthers says, “ The plants were true cryp: ceeds to its conclusion, to demonstrate to the botanical togams, and in their organisation agree in every essential world that I have abundant reason for so doing. This is point with the stems of Lycopodiaceæ” (NATURE, P. 337). a question wholly resting upon facts, and until those facts With this I of course agree, but I contend that we must are fairly before the world, i object to the adoption of any interpret the lower forms by the higher and not the higher a priori conclusion on the subject. Consistently with his by the lower. In Carboniferous ages, these plants became views Mr. Carruthers objects to my applying to the stems in superb forest trees, and consequently their stems attained question such terms as medulla and medullary rays; especitheir full development, growing year after year, from their ally objecting to the application of the term medulla to a almost microscopic condition when they burst from a mi- structure containing vessels, i.e., a vascular medulla ; but croscopic spore, until they became stately trees, such as Nepenthes has a vascular medulla, as well as some other were revealed at Dixon Fold, and such as are illustrated phanerogamous plants, and no one presumes to deny the by specimens now in the Manchester Museum. In the medullary character of such a tissue, because it happens course of their magnificent development the stems were to have vessels in it. The medullary character of the gradually fitted to sustain an enormous weight of branch structure does not rest upon the basis of its being wholly and foliage. This was done by the development, within | devoid of vessels, neither does their occasional presence those stems, of a vascular woody cylinder, which grew militate against its being a medulla. thicker year by year ; such thickening being the result of In the preceding remarks I have confined myself subadditions to the exterior of the previous growths. We here stantially to the task of making clear the points at issue come to a definite issue. Do my opponents intend to between my opponents and myself. In adopting my deny the existence, in these arborescent carboniserous views of the exogenous structure of the stems in question, plants, of these thick ligneous cylinders, or to dispute that I am but following in the steps of some of the ablest of they grew in the way described ? I think they cannot | living botanists. M. Adolphe Brongniart, than whom no possibly contemplate doing so. Dr. M‘Nab says botanists higher authority can be named, not only adopts the are agreed in this, that " Lepidodendra and their allies exogenous theory, but is so deeply impressed with its force are closely related to other Lycopods. Now we know that he denies the probability of many of the plants in that the Lycopods, like the Ferns, have closed fibro. question having been cryptogamic. He places them vascular bundles; bundles which can only grow for a amongst the gymnospermous exogens. Recent events, certain time, and then, all the cambium being converted however, have shown that though exogenous they are true into permanent tissue, growth must cease.” The italics cryptogams. How absurd, then, to apply to such stems in the preceding paragraph are my own. With the above the term acrogen or acrobrya! This controversy must remark, so far as Ferns are concerned, I thoroughly agree. be ultimately settled by the logic of facts, not by yague The facts so correctly stated by Dr. M‘Nab constitute opinions, and to these i confidently appeal. The details one of the fundamental bases of my proposed classifica of my proposed classification can only be discussed when tion. The vascular bundles are closed in all the small all the facts are before the public. When this is the case, ferns, and they remain equally so in the Cyatheas and I hope to show that my proposition not only does no other arborescent ferns which attain to stately dimensions. violence to the true affinities of living cryptogams, but that, The development of this type into a lofty tree has not in bringing the ancient and modern types into a philosomaterially modified the structure of the stem which recurs phical relationship, it accomplishes what, under existing in the most dwarsed species. But when Dr. M'Nab systems of classification, it is impossible to do. applies the above general statement to the Lycopods,
W. C. WILLIAMSON ; METEOROLOGY IN AMERICA *
It may be added that, without distinction of party, the II.- ORGANISATION OF THE UNITED STATES SIGNAL Congress, and the President, have earnestly sustained
whole people of the country, the press, both Houses of SERVICE.
and advanced this important branch of the public service. THERE are probably few departments of the Executive The military system is one of the most valuable fea.
of the United States which have been of such tures in the constitution of this Signal Service for the essential practical value as the Signal Service ; and benefit of Commerce. The advantages of having the among those who have been instrumental in establishing whole corps of weather observers in the army are manifest it, we cannot avoid mentioning the names of the Hon. and manifold. Each observer feels the responsibility of a Halbert E. Paine of Wisconsin, the Hon. Henry L. sentinel at his post, which begets in him a sentiment of Dawes of Massachusetts, and the Hon. William w. devotion to duty the strongest of which men are capable, Belknap, Secretary of War.
and which has often led the soldier to imitate the example
of the Roman guard at Pompeii, who, after nearly eighteen cations of their instruments, and to transmit the same centuries, was taken from its ruins in his martial position, without delay or inaccuracy. In doing this work, they showing that he had not fled before the molten flood from have become by tri-daily practice as expert and exact in Vesuvius. Experience has proved what the sense of the reading the glasses as any of our veteran scientific menGovernment originally suggested, that observations would indeed, as much so as a Fitzroy or a Leverrier could be. be most punctually and scrupulously taken at the different Regarding the Signal Corps scattered through and over stations by men accustomed to the discipline and obe- all parts of the country, we may compare it to a regiment dience, even in minutest details, of army subalterns. on drill three times a day, the telegraph instantly revealing
They are required to work out no difficult problems in to the commanding officer, General Albert J. Myer, at meteorology, but simply to observe and record the indi- Washington, the slightest failure in any observer. * We are again indebted to Harper's Weekly for the continuation of the
By this now widely spread and magnificently organised article by Prof. Maury, and the woodcuts which we reproduce this week. system, the United States army, engaged under the chief