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a doubt could occur to the mind of any intelligent reader, reduced heights being invariably employed in the chapter in which the passage occurs, and in the book generally.

The charge of inconsistency which the Reviewer urges with so much gusto, is based on the following passage in my Preface, at the beginning of Part I:

"There is great danger in the present day lest science-teaching should degenerate into the accumulation of disconnected facts and unexplained formule, which burden the memory without cultivating the understanding. Prof. Deschanel has been eminently successful in exhibiting facts in their mutual connection; and his applications of algebra are always jud cious."

Which, the Reviewer thinks, justified the expectation that I would omit as many as possible of Deschanel's applications of Algebra. It is not surprising that a writer accustomed to this style of inference should have an aversion to exact reasoning, and should characterise the solution of problems by the application of a little algebra as "intricate formulæ, which burden the memory without cultivating the understanding."

I may remark, with reference to my former discussion with W. M. W. in your pages, that the adoption of concrete units of mass, and derived units of force, has now received the official sanction of Sections A and G of the British Association, who have appointed a committee to frame a system of nomenclature on this basis. J. D. EVERETT

Newspaper Science

KNOCKED up with work, I reluctantly followed the advice of my medical man, and crossing the Channel so as to be more out of the way, resolved to eschew everything scientific for the next few weeks at least, in order to recruit before the winter's labours

commenced. Even here, however, I soon found that the desired result was not so easily attainable as I had imagined, for the first thing this morning, on entering the reading room of the bathing saloon, a French acquaintance, placing the Globe (of Monday evening, September 11) before me, directed my attention to its leading article on Prussian Artillery, adding significantly-"Violà, mon ami, a specimen of English scientific opinion!"

I must confess that it was not without a feeling of shame that I read an article, of which the following extracts will suffice to give a correct idea.

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"Although the unchequered course of the late war was due to many causes, still it is now admitted on all sides that when the Krupp guns were brought into the field the conclusion was practically foregone. "The first public exhibition of what is now known as the Krupp gun was the gigantic specimen of a breechloading steel gun sent to our Exhibition of 1851. The steel of which this gun was made differs entirely from our Sheffield gun metal or from Bessemer metal, and is a composition invented by Krupp, and the result of a special process. The iron is alloyed with certain clays and also with a preparation of plumbago. There are 100,000 'creusets' of this metal always in active employment in the factory, and each 'creuset' contains from twenty to forty kilogrammes. The metal in a fluid state is poured into large cylindrical moulds, where it remains for two hours till it has completely hardened. But the chief difficulties of the process lie in subjecting it to the steam hammer. For years the hammer of greatest power in the factory had a force of 25,000 kilometres," &c. !

The italics are mine, and any one conversant with such subjects will perceive that no further comments are required. It only remains for me to express my astonishment at seeing such rubbish appear in the leading article of any newspaper of standing, and I am sure your readers will agree with me that it is high time that journals specially devoted to science should protest energetically against such representations being conveyed to the public at home and abroad as expressions of English technical or scientific opinion. DAVID FORBES

Boulogne-sur-Mer, September 13

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the fossil teeth (from the Jurassic and Triassic formations) known under the name of Ceratodus.

The interest attached to such a discovery will be easily understood, if we review briefly the history of Lepidosiren, and show the advance made by zoology in consequence of our acquaintance with this animal.

The discovery is due to the well-known Austrian traveller, Natterer, who sent two examples from Villa Nova on the Amazon River and the Rio Madeira to the Vienna Museum in the year 1837. Fitzinger, then Curator of the Collection of Reptiles, gave a somewhat superficial description of it under the name of Lepidosiren paradoxa, referring it without hesitation to the class of Reptiles. Nearly at the same time a very similar`animal was found by Mr. Th. C. B. Weir, in Senegambia; he presented two small examples to the Royal College of Surgeons; and Prof. Owen, then Curator of the Hunterian Museum, published a full description of them under the name of Lepidosiren annectens, in the year 1839, explaining the reasons which induced him to regard this creature as a Fish. This view elicited further examination of the internal structure of the American species by Profs. Bischoff and Hyrtl, the former inclining to the opinion expressed by Fitzinger, the latter confirming, to the satisfaction of nearly all zoologists, the correctness of the conclusion arrived at by Owen.

Before the discovery of Lepiaosiren, zoologists distinguished the class of Reptilia from that of Fishes by the organ of respiration, the former being provided with membranous lungs extending into the abdominal cavity, the latter breathing by gills only. Although the Batrachian reptiles were known to breathe by external gils, as fishes, during the early stage of their metamorphosis, and although some of them retain those gills through the whole period of their life, yet the development of lungs in the adult state and the co-existence of these organs with gills in the Perennibranchiates, were considered to be sufficient indications of their class-distinctness from fishes, among which no air-breathing organ was known. It is true Harvey and Hunter had pointed out that the air-bladder of the fish was homologous with the lung of higher vertebrates; but functionally it could not be compared to it, as it receives arterial blood like any other abdominal organ, returning it in a deoxygenised condition.

Now Lepido iren was found to be provided with gills, and a most perfect paired lung communicating by a ductus pneumaticus and glottis with the oesophagus, receiving venous blood by strong arteries, and sending it back directly to the heart in an oxygenised condition. Therefore, in this respect it did not differ from an Amphibian, and dogmatical believers in the stability of our zoological systems felt themselves quite justified in referring this creature to the Reptilians.

Nevertheless, the presence of certain other peculiarities of structure indicated rather an ichthyic than a reptilian affinity. The notochordal skeleton, and the apophyses arranged as in many fishes, and not as in Amphibians; the organ of hearing enclosed in the cartilaginous capsule of the skull; the dentition extremely similar to that of a Chimæra; the intestinal tract traversed by a spiral valve; peritoneal outlets near the vent; no nasal canal to conduct air; finally, the skin covered with scales, the fins supported by fin rays. All these are characters not found in Batrachians, and connect Lepidosiren with the class of Fishes; but it was admitted that it makes the nearest approach in that class to the Perennibranchiate Amphibians.

The question had next to be settled, what place in the class of Fishes should be assigned to Lepidosiren; and as the view entertained by Joh. Müller is that adopted by the majority of zoologists, we think it sufficient to refer to it alone. Having determined that all Ganoid Fishes agree with the Sharks and Rays in having an additional muscular division of the heart at the origin of the aorta, named bulbus

arteriosus, and provided with transverse series of valves in its interior, he found that such a bulbus arteriosus was likewise present in Lepidosiren, but with a very different valvular arrangement. This peculiarity, combined with the development of a lung, he considered to be sufficient to distinguish Lepidosiren as the type of a separate subclass, which he named Dipnoi, and placed at the head of the entire class.

Thus, then, Lepidosiren was finally placed among the Fishes; but from the time of its discovery dates the tendency of zoologists to subdivide the assemblage of coldblooded animals not only where the development of a lung ceases, but also where the development of gills begins. Or, in other words, systematists became more and more convinced that the old division of Reptiles and Fishes was insufficient, and that three classes of living cold-blooded Vertebrates should be distinguished, viz., Reptiles, Amphibians, and Fishes, some regarding the second as even more closely allied to the third than to the first.

When we find a group of animals represented by a very small number of forms in the existing Fauna, we look to Paleontology to fill up the seeming blanks; but Lepidosiren did not appear to have any fossil representatives. Prof. Owen stated (in 1839) that its teeth resembled "in their paucity, relative size, and mode of fixation to the maxillæ, those of the Chimæra and some of the extinct cartilaginous fishes, as Cochliodus and Ceratodus,;" but no further inference was made from this fact as regards affinity. And Prof. Huxley (in 1861), when drawing attention to analogous structures in Lepidosiren and certain Devonian fishes, still maintained the entire absence of the Dipnoous type in the fossil state.

The discovery of a "gigantic Amphibian allied to the genus Lepidosiren, from rivers in Queensland," and named Ceratodus Forsteri by Mr. Krefft, promised to mark another step in the advancement of our knowledge, and to lend additional aid in determining the natural affinities of these animals. As soon as Mr. Krefft had recognised the importance of this discovery, the trustees of the Australian Museum of Sydney took steps to secure well-preserved examples. They sent a collector into the district where the animal was known to occur; and, with their usual liberality, they despatched to the British Museum, for examination, the first specimens they could spare, by which I was enabled to present a full account of its organisation to the Royal Society. It is not my intention to enter here into the details of the results of this examination; I must be satisfied with giving a short description of it, pointing out some of the bearings which this discovery has upon the advancement of science.

The fish (for this it proved to be, and even more so than Lepidosiren) appears to be not uncommon in some districts of Queensland; specimens have been obtained from the Burnett, Dawson, and Mary rivers, some high up in perfectly fresh water, others descending into the lower brackish portions. It is said to grow to a length of six feet, the largest example sent to the British Museum being about three and a half feet long. The flesh is excellent eating, and of salmon colour, hence it is called by the squatters Burnett or Dawson salmon. Its food consists of the decaying leaves of myrtaceous and other plants, with which the stomach and intestine are crammed. Probably now and then it swallows, perhaps accidentally, some aquatic animal; but it is rather doubtful whether it can be caught by using living animals as bait. It is also stated that it is in the habit of going on land, or at least on mud-flats; and this assertion appears to be borne out by the fact that it is provided with a true lung. On the other hand, we must recollect that a similar belief was entertained with regard to Lepidosiren, of which now numerous examples have been kept in captivity, but none have shown a tendency to leave the water. I think it much more probable that this animal rises now and then to the surface of the water, in order to fill its lungs with

air, and then descends again until the air is so much deoxygenised as to render a renewal of it necessary. When we recollect that the animal evidently lives in mud or in water charged with the gases which are the product of decomposing organic matter, the usefulness or necessity of such an air-breathing apparatus, additional to the gills, becomes at once apparent. Further we shall see that the limbs of this unwieldy and heavy animal are much too feeble and flexible to be of much use in locomotion on land; they may assist it in its crawling, in water, over the muddy bottom of a creek; but the chief organ of locomotion is the compressed, broad, and flexible tail, denoting by its shape and structure that the fish can execute rapid swimming motions. However, it is quite possible that it is occasionally compelled to leave the water, although I do not believe that it can exist without it in a lively condition for any length of time. It is said to make a grunting noise, which may be heard at night for some distance. This noise may be produced by the passage of the air through the oesophagus, when it is expelled for the purpose of renewal.

It deposits a great number of small eggs, which are impregnated after deposition. Nothing is known of their development; but we may infer that the young are provided with external gills, like those of some other Ganoid Fishes.

The Barramunda (we will use the name given to it and other similar fishes by the natives) is eel-shaped, but considerably shorter and thicker than a common eel, and covered with very large scales. The head is flattened and broad, the eye lateral and rather small, the mouth in front of the broad snout and moderately wide. The gill openings are a rather narrow slit on each side of the head. There are no external nostrils. The tail, which is of about the same length as the body without the head, is compressed, and tapers to a point, but it is surrounded by a very broad fringe, supported by innumerable fine and long fin-rays. There are two fore and two hind paddles, similar to each other in shape and size, and very different from the fins of ordinary fishes; their central portion being covered with a scaly skin, and the entire paddle surrounded by a rayed fringe. If we were to cut off the hind part of the tail of a fish, the piece would bear a strong resemblance to one of the paired paddles. The vent is situated in the median line of the abdomen between the paddles.

In order to obtain a view of the inside of the mouth, it is necessary to slit it open, at least on one side. We then notice that there are a pair of nasal openings within and on each side of the cavity of the mouth. The palate is armed with a pair of large, long, dental plates, with a flattish, undulated, and punctated surface, and with five or six sharp prongs on the outer side, entirely similar to the fossil teeth described under the name of Ceratodus. Two similar dental plates of the lower jaw correspond to the upper, their undulated surface fitting exactly to that of the opposite teeth. Beside these molars the front part of the upper jaw (vomer) is armed with two obliquely placed incisor-like dental lamellæ, which have no corresponding teeth in the lower jaw. As we know the kind of food taken by the Barramunda, the use of their teeth is apparent. The incisors will assist in taking up, or even tearing off, leaves, which are then partially crushed between the undulated surfaces of the molars.

The skeleton consists of a cartilaginous basis, in the form of a long tapering chord for the body and tail, and in that of a capsule for the head. No segmentation into separate vertebræ is visible in any part of the notochord but it supports a considerable number of apophyses, the abdominal of which bear well developed ribs, all being solid cartilaginous rods, with a thin sheath of bone. In the same manner no part of the brain-capsule is ossified, but it is nearly entirely enclosed in thin bony lamellæ. This is also the structure of the appendages of the skull,

as the mandible and the hyoid and scapulary arches. From a study of the skull, it becomes apparent at once why in fossil teeth of Ceratodus nothing or very little of the bone attached to them has been preserved. Those teeth rest on cartilage as well as on bone, the latter being a very thin and porous layer which could not be preserved, unless the progress of stratification had been going on with as little disturbance as in the Solenhofen Schiefers; but the matrix in which fossil Ceratodont teeth are found shows that it was formed under very different conditions, and it is certainly not of a nature to permit the supposition that thin porous lamella of bone would have been preserved entire.

The structure of the skeleton reminds us much of that of the sturgeons, Chimæra, and especially of Lepidosiren; and of all the modifications by which it differs from these types, perhaps none is of greater interest than that observed in the paddles. The central part of the paddle, which we have found externally to be covered with scales, is supported by a jointed axis of cartilage extending from the root to the extremity of the paddle; each joint bears a pair of three- or two- or one-jointed branches. This is the case in the hind as well as fore paddles, and we are justified in supposing that those extinct Ganoids of which impressions of paddles with scaly centres have been preserved, were provided with a similar internal skeleton. Professor Huxley, some years ago, drew attention to the analogy existing between the filamentary limbs of Lepidosiren and the lobate fins of certain extinct Ganoids, and the correctness of this view is fully borne out by the discovery of Ceratodus, inasmuch as the Lepidosiren limb proves to be typically the same as that of Ceratodus, but reduced to the jointed central axis.

The gills are perfectly developed, four on each side. They are broad lamellated membranes, free from each other, but attached to the outer walls of the gill-cavity. One can hardly doubt that, in water of normal composition, they are sufficient for the purpose of breathing. A 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 Barramunda is in water sufficiently pure to yield the necessary supply of oxygen, the function of breathing rests with the gills alone, and the lung receives arterial blood, returning venous blood, like all the other organs of the body; under this condition it does not differ from the air-bladder of other fishes. But when the fish is compelled to sojourn in thick muddy water, charged with noxious gases, which must be the case very frequently during the droughts which annually exhaust the creeks of tropical Australia, it commences to breathe air in the way indicated above, under this condition the pulmonary vein carries purely arterial blood to the heart, where it is mixed with venous blood and distributed to the various organs of the body. If the medium in which the fish happens to be is perfectly unfit for breathing, the gills cease to have any function; if only in a less degree, the gills may still continue to assist in respiration. In short, the organisation of the Barramunda is such as to justify us in the assertion that it can breathe by either gills or lung alone, or by both simultaneously.

With regard to the structure of the lung, it shows a nearer approach to the air-bladder of other living Ganoid fishes than that of Lepidosiren; it is not paired, but consists of a single long sac extending nearly to the end of the abdominal cavity. Yet the interior of the sac shows a symmetrical arrangement of the right and left side, being subdivided into numerous cellular compartments, by which the respiratory surface is much increased in extent.

The next organ of importance for determining the systematic affinities of the Barramunda is the heart. Considering the great resemblance this fish has shown in other respects to Lepidosiren, I fully expected to find this organ agree also with the Dipnoous type; but this is not

the case.

Instead of the two longitudinal valves of the Dipnoous heart, the bulbus arteriosus is provided with two or three transverse series, of which one only is fully developed; or, in other words, Ceratodus proved to be a Ganoid fish. But, as Ceratodus and Lepidosiren are in all other points too closely allied to be separated in two distinct sub-classes or even sub-orders, we must arrive at the conclusion to drop the Dipnoi as a sub-class, and to refer Lepidosiren also to the Ganoids, which will then be characterised, not by transverse series of valves, but by the presence of a muscular, contractile bulbus arteriosus with valves, transverse or longitudinal, in its interior- a structure which they have in common with the sharks and rays (Plagiostomata).

The intestinal tract is a large straight sac with an internal spiral valve, as in the Ganoids and Plagiostomes. The kidneys are paired, the ureters enter a very small urine bladder or cloaca at the back of, and partly confluent with, the rectum.

The organs of propagation show some noteworthy peculiarities. They are paired, in long bands. The male organs have no visible outlet, although a seminiferous duct has been found traversing the substance of the testicle through nearly its whole length; no outward opening could be discovered, and it is not known how the semen is discharged. The ova are small, very numerous, and attached to transverse laminæ of the ovaries; when mature, they fall into the abdominal cavity, as in the salmon tribe, and would appear to be expelled through two wide slits behind the vent. Yet each ovary is accompanied by a long oviduct, as in the sturgeon or Lepidosiren, though it probably has no function, and is only indicative of an approximation of this remarkable fish to higher types. Such are some of the principle features of the organisation of the Barramunda; and it remains now to add some remarks on its affinities and its place in the system. A. GÜNTHER

(To be continued.)

ON EXOGENOUS STRUCTURES AMONGST THE STEMS OF THE COAL-MEASURES

IN

N a memoir recently read before the Royal Society, I propounded a new classification of the vascular cryptogams, and at the late meeting of the British Association at Edinburgh I brought the same subject forward, when my views were opposed by Mr. Carruthers, Dr. M‘Nab, and Prof. Dyer, as reported in the columns of NATURE for Aug. 31. I was well aware that when I disturbed existing and time-honoured systems of classification I should meet with such opposition; but, being thoroughly convinced that my views are sound, and that they will ultimately be adopted, it only remains for me to face the conflict, and persevere with my demonstrations of what I believe to be true. My present object is to do what was impossible in the hurried and unsatisfactory discussions that frequently arose at the meetings of the British Association to accomplish, viz.: to take care that there shall be no misunderstanding as to the real points at issue. My opponents seek to interpret the gigantic arborescent stems of the coal measures by the light of the dwarfed and degraded examples of vascular cryptogams which constitute their living representatives. I, on the other hand, claim to interpret the latter by the former, some of which, the Lycopods, for example, instead of being feeble things trailing in the grass, had stems three feet in diameter, and rising a hundred feet into the air Instead of merely constituting a verdant carpet for forests of noble exogens and endogens, they were the forest; here, consequently, we might expect that whatever characteristic features they possessed would be developed and displayed in their utmost perfection.

Mr. Carruthers' fundamental argument is, that I, in my

classification, elevate the vegetative organs at the cost of the reproductive ones. I reply I am merely applying principles already adopted by botanists throughout the world. They are those of DeCandolle, of Endlicher, of Lindley, of Brongniart, and of Balfour. These writers, in common with most others, recognise primary distinctions that are purely vegetative. Not only are those which separate vascular from cellular plants of this character, but the further ones of exogens, endogens, acrogens, and thallogens are of the same nature. The fact of the closest resemblance of the inflorescence, and of the formation of the embryo in the embryo-sac in the two groups, does not prevent the separation of the flowering plants into exogens and endogens. Turning from the phanerogamous to the cryptogamic plants, we find that nearly every writer of importance adopts vegetative features as the basis of his classification. DeCandolle divides his Acrogens into those which have and those which have not vascular tissues. Endlicher's primary term Cormaphyla refers to a vegetative feature, viz., the possession of a stem, whilst his secondary divisions of Acrobrya, Amphibrya, and Acramphibrya all refer to the mode of growth and not to fructification. Lindley again distinguishes his flowerless plants according as they are acrogens or thallogens; whilst Balfour characterises them primarily as acrogens or cormogens and thallogens. In thus dwelling upon the vegetative element of the cryptogams, I am merely treading in the steps of nearly every writer of note who has written on these subjects. So much, therefore, for the primary point.

In many of the discussions which have taken place, my opponents have made the mistake of supposing that I was trying to prove these fossil coal-plants to be dicotyledonous exogens. Whereas what I have throughout contended for is that they are true cryptogams with an exogenous woody axis. Mr. Carruthers says, "The plants were true cryptogams, and in their organisation agree in every essential point with the stems of Lycopodiacea" (NATURE, p. 337). With this I of course agree, but I contend that we must interpret the lower forms by the higher and not the higher by the lower. In Carboniferous ages, these plants became superb forest trees, and consequently their stems attained their full development, growing year after year, from their almost microscopic condition when they burst from a microscopic spore, until they became stately trees, such as were revealed at Dixon Fold, and such as are illustrated by specimens now in the Manchester Museum. In the course of their magnificent development the stems were gradually fitted to sustain an enormous weight of branch and foliage. This was done by the development, within those stems, of a vascular woody cylinder, which grew thicker year by year; such thickening being the result of additions to the exterior of the previous growths. We here come to a definite issue. Do my opponents intend to deny the existence, in these arborescent carboniferous plants, of these thick ligneous cylinders, or to dispute that they grew in the way described? I think they cannot possibly contemplate doing so. Dr. M'Nab says botanists are agreed in this, that "Lepidodendra and their allies are closely related to other Lycopods. Now we know that the Lycopods, like the Ferns, have closed fibrovascular bundles; bundles which can only grow for a certain time, and then, all the cambium being converted into permanent tissue, growth must cease." The italics in the preceding paragraph are my own. With the above remark, so far as Ferns are concerned, I thoroughly agree. The facts so correctly stated by Dr. M'Nab constitute one of the fundamental bases of my proposed classification. The vascular bundles are closed in all the small ferns, and they remain equally so in the Cyatheas and other arborescent ferns which attain to stately dimensions. The development of this type into a lofty tree has not materially modified the structure of the stem which recurs in the most dwarfed species. But when Dr. M'Nab applies the above general statement to the Lycopods,

facts do not sustain him. The huge lepidodendroid carboniferous plants give it a direct contradiction. They have not closed vascular bundles, and their growth did not cease after a limited time, but was obviously continued, being sustained by a cambium layer, until the plants assumed the magnificent dimensions which their fossil remains now exhibit. That the large vascular cylinder of the fossil forms is a development of what is seen, not only in Lycopodium chamaecyparinus referred to by Dr. M'Nab, but in every one of the numerous Lycopods of which I have examined sections, I have never denied. Quite the contrary. But I repeat we must interpret the significance of the least developed form by that which is most developed. Consequently we must regard the irregular vascular bundles which exist, commingled with cellular tissues, in the axis of each living Lycopod, as a degraded wood cylinder, whose nature can only be understood by reference to what it once was when its parent tree was one of the glories of the primæval forest. The race as a whole has become degenerate, and the stem being no longer called upon to sustain a lofty superstructure, its structure has become equally degenerate. I will not enter in detail into the question of the nomenclature of the various parts of these exogenous cryptogamic stems, but reserve that subject for some other occasion, after my detailed memoirs now in the hands of the Royal Society have been published. I will merely express my conviction that Mr. Carruthers, who differs widely from me on the subject, assumes the very question in debate between us.

He holds that we can draw no parallel between the conditions existing in the stems of Cryptogams and those of Phanerogams. This is precisely what I contend we can do, and I trust to be able, as my self-appointed task proceeds to its conclusion, to demonstrate to the botanical world that I have abundant reason for so doing. This is a question wholly resting upon facts, and until those facts are fairly before the world, I object to the adoption of any a priori conclusion on the subject. Consistently with his views Mr. Carruthers objects to my applying to the stems in question such terms as medulla and medullary rays; especially objecting to the application of the term medulla to a structure containing vessels, ie., a vascular medulla; but Nepenthes has a vascular medulla, as well as some other phanerogamous plants, and no one presumes to deny the medullary character of such a tissue, because it happens to have vessels in it. The medullary character of the structure does not rest upon the basis of its being wholly devoid of vessels, neither does their occasional presence militate against its being a medulla.

In the preceding remarks I have confined myself substantially to the task of making clear the points at issue between my opponents and myself. In adopting my views of the exogenous structure of the stems in question, I am but following in the steps of some of the ablest of living botanists. M. Adolphe Brongniart, than whom no higher authority can be named, not only adopts the exogenous theory, but is so deeply impressed with its force that he denies the probability of many of the plants in question having been cryptogamic. He places them amongst the gymnospermous exogens. Recent events, however, have shown that though exogenous they are true cryptogams. How absurd, then, to apply to such stems the term acrogen or acrobrya! This controversy must be ultimately settled by the logic of facts, not by vague opinions, and to these I confidently appeal. The details of my proposed classification can only be discussed when all the facts are before the public. When this is the case, I hope to show that my proposition not only does no violence to the true affinities of living cryptogams, but that, in bringing the ancient and modern types into a philosophical relationship, it accomplishes what, under existing systems of classification, it is impossible to do.

W. C. WILLIAMSON ;

METEOROLOGY IN AMERICA *

II.-ORGANISATION OF THE UNITED STATES SIGNAL whole people of the country, the press, both Houses of

SERVICE.

THERE are probably few departments of the Executive of the United States which have been of such essential practical value as the Signal Service; and among those who have been instrumental in establishing it, we cannot avoid mentioning the names of the Hon. Halbert E. Paine of Wisconsin, the Hon. Henry L. Dawes of Massachusetts, and the Hon. William W. Belknap, Secretary of War.

It may be added that, without distinction of party, the Congress, and the President, have earnestly sustained and advanced this important branch of the public service. The military system is one of the most valuable features in the constitution of this Signal Service for the benefit of Commerce. The advantages of having the whole corps of weather observers in the army are manifest and manifold. Each observer feels the responsibility of a sentinel at his post, which begets in him a sentiment of devotion to duty the strongest of which men are capable, and which has often led the soldier to imitate the example

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of the Roman guard at Pompeii, who, after nearly eighteen centuries, was taken from its ruins in his martial position, showing that he had not fled before the molten flood from Vesuvius. Experience has proved what the sense of the Government originally suggested, that observations would be most punctually and scrupulously taken at the different stations by men accustomed to the discipline and obedience, even in minutest details, of army subalterns. They are required to work out no difficult problems in meteorology, but simply to observe and record the indi*We are again indebted to Harper's Weekly for the continuation of the article by Prof. Maury, and the woodcuts which we reproduce this week.

cations of their instruments, and to transmit the same without delay or inaccuracy. In doing this work, they have become by tri-daily practice as expert and exact in reading the glasses as any of our veteran scientific menindeed, as much so as a Fitzroy or a Leverrier could be.

Regarding the Signal Corps scattered through and over all parts of the country, we may compare it to a regiment on drill three times a day, the telegraph instantly revealing to the commanding officer, General Albert J. Myer, at Washington, the slightest failure in any observer.

By this now widely spread and magnificently organised system, the United States army, engaged under the chief

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