tures up to 60° C., is described and figured at p. 348, and consists essentially of a closed vessel with triple walls, the space between the inner and middle plate filled with water, the outer containing air. For higher temperatures a simple tin plate thermostat was employed, the space being filled with water for temperatures up to 100° Cent. and with glycerine or oil for higher temperatures. The source of heat was always a gas-flame with the usual thermo-regulator. Numerous tabulated results are given of experiments upon moist and dry seeds at various temperatures, and it was found, as might be anticipated, that perfectly dry seeds can withstand a high temperature, even between 120° and 125° Cent., without injury.

Dr. Koch describes how bacteria can be observed, prepared, and photographed, this paper forming the sixth of the extremely important series of researches on bacteria which have from time to time appeared in the Beiträge. A thin layer of bacteria with the fluid containing them is to be dried on a thin cover of glass. By placing the glass cover with the dried material in absolute alcohol, or better, in a 0'5 per cent. solution of chromic acid, the bacteria are fixed to the cover, although the coagulated ground substance in which the bacteria are imbedded can be made to swell up and the bacteria themselves to resume their natural forms when the cover is placed in a solution of acetate of potash (1 part to 2 of distilled water). The bacteria can be coloured by means of aniline, the best of all being aniline brown; but methyl violet and fuchsin will also answer. The stained object can be preserved permanently on slides by mounting in Canada balsam, concentrated solution of acetate of potash, or in glycerine. Twenty-four photographs of bacteria, mostly from specimens stained with aniline brown, illustrate the paper; and in some, as 5 and 6 on Plate XIV., the cilia of bacillus are very beautifully shown, magnified 500 and 700 diameters. Koch finds that it is easier to photograph the cilia than to observe them directly with the microscope.

The other papers in this part are on certain Ustilaginæ, by Dr. Schroeter; and on two new species of Entomophthora (E. conglomerata and E. rimosa) discovered upon dead gnats, by Prof. N. Sorokin.

The first and second parts of vol. iii. contain eleven papers. Four of these are devoted to Bacteria, and form the seventh to the tenth of the series of Researches on Bacteria already alluded to. The titles of the papers are VII. Experiments on Infection with Micrococcus prodigiosus, by Dr. A. Wernich; VIII. Researches on the Bacteria in Air, by Dr. Miflet; IX. On the Action of the Electrical Current on the Multiplication of Bacteria, by Dr. F. Cohn and Dr. Mendelssohn; and X. Studies of Blue Milk, by Dr. F. Neelsen. Two of these papers may be briefly mentioned. By means of a specially contrived apparatus fitted with a new continuous aspirator, the invention of Paul Boehme in Brunn, atmospheric air from different localities was examined. These were (1) air in Botanical Laboratory; (2) in Fever Hospital; (3) in the Pathological Theatre; (4) in the Surgical Theatre; (5) air in Botanic Garden; (6) air for soil; and (7) air for drains. The results were briefly as follows:-1. Germs of bacteria capable of developing are abundant in the air, and could readily be collected and cultivated in a special mineral solution, malt extract, or solution of Liebig's

extract of beef. 2. Many forms of bacteria can produce reproductive germs in air, while others, as B. Termo, seein only capable of producing germs in putrescent matter. 3. Air from the soil contained occasionally germs of bacteria. 4. Air from the Fever Hospital contained no germs, owing to the completeness of the ventilation and disinfection. 5. Air from a sewer contained abundance of germs of bacteria capable of reproducing.

Neelsen, in his paper on Blue Milk, finds that the special organism in it may assume three or four different forms, sometimes like Bacterium, then like Bacillus, then like a Chroococcus, and lastly like a Leptothrix. He discusses the Theory of Cohn and others that the Bacteria form many separate genera and species, and the Theory of Lankester and Warming, that they are forms of a protean species, and seems to conclude that the germs of a given form may under different conditions develop in one or other direction, as observed by him in blue milk.

Dr. Schroeter continues his observations on the Development of Rust, and Dr. Oscar Kirchner describes the Development of Volvox minor, Stein. Dr. Hielsher describes the Anatomy and Biology of the Genus Streptocarpus, and details many interesting facts regarding that curious and beautiful genus. When the seed of Streptocarpus polyanthus germinates, numerous adventitious roots form on the primary axis, one of the two cotyledons soon disappears, while the other develops greatly, and forms a perennial foliage leaf. On the petiole of this leaf numerous adventitious roots develop and the primary axis disappears. The leaf produces adventitious buds from which the flowers develop, while it also develops a series of adventitious leaf-buds. Dr. Beinling contributes a paper on the formation of adventitious roots and buds on the leaf-cuttings of Peperomia. Prof. Klein describes in detail the anatomy of Pinguicula alpina as an insectivorous plant, and points out that the plant occurs in two forms, one with green leaves, the other with the leaves more or less red-brown in colour, and that the tissues assume an intense yellow colour when acted on with caústic potash solution. The remaining papers are by Dr. Schwartz, Chemico-botanical Studies on the Acids in Lichens, and Dr. Eidam on the Gymnoasci. The various papers ably sustain the reputation of this work, and all of them will well repay careful study.

LETTERS TO THE EDITOR

[The Editor does not hold himself responsible for opinions expressed by his correspondents. Neither can he undertake to return, or to correspond with the writers of, rejected manuscripts. N notice is taken of anonymous communications. The Editor urgently requests correspondents to keep their letters as short as possible. The pressure on his space is so great that it is impossible otherwise to ensure the appearance even of communications containing interesting and novel facts.]

Dust and Fogs

I MUCH regret the Hon. R. Russell, in his letter to NATURE, vol. xxiii. p. 267, takes such an extremely desponding view of the influence which my experiments on cloudy condensation are likely to exercise upon the present attempts to rid the atmosphere of our large towns of their ever-recurring fogs. The object of these experiments was to find out what caused fogs, in the hope that with the knowledge thus acquired we might be better able to find a remedy. The preferable course seemed to be to find the cause first, and then if possible devise some remedy, rather than try remedies at haphazard.

It is certainly very far from my desire to discourage the present attempts which are being made to clear the atmosphere of our large towns of smoke, and I have recognised the advantages which would result from the adoption of more perfect forms of combustion. In my paper I have simply distinguished between fogs and smoke, and separated them for distinct consideration and treatment, and have at the same time directed attention to some points which ought to be considered before deciding on their prevention.

With regard to Mr. Russell's difficulty in reconciling the result of the experiments with what is observed with regard to fogs in London, Paris, and other large towns, it appears to me to have arisen entirely from not putting sufficient weight on the allimportant influence of the amount of vapour in the air of the different places. It is condensed vapour which forms the fog, and dust simply determines whether it will condense in fine- or coarse-grained particles. The atmosphere of Paris, compared with that of London, is an extremely dry one, and the air is seldom in a condition to produce fogs. The atmospheres of the other towns mentioned are also drier, some of them very much drier, than that of London. London however will probably be always more subject to fogs than other cities on account of its great size, some part of it being always in its own smoke.

Considered from a different point of view, might not the fog of January 31, 1880, referred to by your correspondent, be cited in evidence of a conclusion the opposite of that drawn by the writer, and in favour of the correctness of the experimental results? From this point of view the low white fog cleared away because it was formed in the comparatively pure air of the streets, while the higher fog did not clear away because it was formed in the products of combustion The true explanation however would rather appear to be, that where the fog was white it was also of less depth than in those places where it "extended high" and mixed with the smoke; and the sun, which was only sufficient to dispel the lesser depth more or less," would evidently be insufficient to clear away the greater depth. It is however impossible to form any definite idea as to how this par ticular fog conducted itself, without much fuller information as to air-current, &c.

I have communicated to the secretary of the Royal Society of Edinburgh a second experimental paper on fogs, with special reference to dry fogs. In this paper the full answer to the latter part of Mr. Russell's letter will be found. JOHN AITKEN Darroch, Falkirk, January 24

Professors Exner and Young

My statement in respect to Prof. Exner's having announced the thermo-electric neutrality of a bismuth-antimony pair immersed in pure nitrogen, rested upon a note in NATURE (vol. xxii. p. 156), and this it seems was based upon a statement in L'Electricité. I have seen those of Prof. Exner's papers which have appeared in the Annalen der Physik, and there is certainly nothing of the sort in them; but I supposed that it must be contained in some other paper in some one of the numerous other publications to which I have not access here. It never occurred to me, until within a very short time, that there could be any mistake as to his having made such an assertion. How or where the error originated I cannot quite understand; but I trust Prof. Exner will accept my apologies for my share in its propagation, and that he and all concerned will be satisfied that no misrepresentation was intended on my part. The incident is a good illustration of the extreme care necessary in commenting upon the views of another person. C. A. YOUNG Princeton, U.S.A., January 12

The Flying-fish

IT is remarkable that there should still be any doubt as to the facts in connection with the flight of the flying-fish. Dr. Günther (“Study of Fishes," p. 622), summarising the observation of Möbius, says that "they frequently overtop each wave, being carried over it by the pressure of the disturbed air" (in the open sea!). Again, flying-fishes "never" fall on board vessels "during a calm or from the lee side." At night "when they are unable to see they frequently fly against the weatherboard, when they are caught by the current of air and carried upwards to a height of twenty feet above the surface of the water." Surely the fish going at the rate of at least ten miles an hour would on striking the "weather-board" be dashed, bruised

and helpless, back into the water instead of coming over the side fresh and vigorous, flapping about on the deck. Except when "by a stroke of its tail" it turns towards the right or left, Möbius concludes that "any deflection from a straight course is due to external circumstances, and not to voluntary action on the part of the fish."

66

I have watched flying-fish repeatedly, and have invariably seen them fly, or rather glide, over the surface of the sea, and from one to two feet above it, rising gently to the swell when there was no wind, and occasionally turning to the right or left without touching the water. I do not say that when there is a breeze the tail of the fish may not touch it, but I think that, with the foam and spray of the broken water, it would be very difficult to be sure of it, and, moreover, if the tail was used the motion would be a jerking one. Mr. Wallace speaks of their 'rising and falling in the most graceful manner," which, although he is referring to another species, applies also to the North Atlantic form (Exocatus evolans). Mr. Bennett ("Gatherings," &c., p. 14) says that they "spring from the sea to a great elevation." This is probably in reference to their coming on board ship at night, attracted, it is supposed, by the lights. I believe the pectoral fins are kept extended without any motion, except perhaps as Mr. Whitman, a recent observer, says, just when they rise from the sea. He gives 800 to 1200 feet as the greatest distance he has seen them fly, and about forty seconds as the longest time out of the water. By what mechanical means they move when out of the water is still to me a mystery.

I have never known the flying fish to be pursued by other fish, nor ever seen any bird near them; indeed few birds are ever seen far from the land north of the southern tropic, where flyingfish are most abundant. The dolphin (Coryphana) is supposed to be their greatest enemy. I had once an opportunity of seeing one opened-in the West Indies-its stomach was quite full of Orthagoriscus mola, very young, being not quite an inch long. FRANCIS P. PASCOE

1, Burlington Road, W., January 21

Mr. S. Butler's "Unconscious Memory"

I MUST reply to the review of my book, "Unconscious Memory," in your issue of the 27th inst., and to Dr. Krause's letter on the same subject in the same issue.

Mr. Romanes accuses me of having made "a vile and abusive attack upon the personal character of a man in the position of Mr. Darwin," which I suppose is Mr. Romanes' way of saying that I have made a vile and abusive personal attack on Mr. Darwin himself. It is true I have attacked Mr. Darwin, but Mr. Romanes has done nothing to show that I was not warranted iu doing so. I said that Mr. Darwin's most important predecessors as writers upon evolution were Buffon, Dr. Erasmus Darwin, Lamarck, and the author of the "Vestiges of Creation." In the first edition of the "Origin of Species" Mr. Darwin did not allude to Buffon nor to Dr. Erasmus Darwin, he hardly mentioned Lamarck, and he ignored the author of the "Vestiges" except in one sentence. This 'sentence was so gross a misrepresentation that it was expunged-silently in later editions. Mr. Romanes does not and cannot deny any part of this.

I said Mr. Darwin tacitly claimed to be the originator of the theory of evolution, which he so mixed up with the theory of "Natural Selection" as to mislead his readers. Mr. Romanes will not gainsay this. Here is the opening sentence of the 'Origin of Species" :

'When on board H.M.S. Beagle as naturalist, I was much struck with certain facts in the distribution of the inhabitants of South America, and in the geological relations of the present to the past inhabitants of that continent. These facts, as will be seen in the latter chapters of this volume, seemed to throw some light on the origin of species; that mystery of mysteries, as it has been termed by one of our greatest philosophers. On my return home it occurred to me in 1837 that something might perhaps be made out on this question by patiently accumulating and reflecting upon all sorts of facts which could possibly have any bearing on it. After five years' work I allowed myself to speculate upon the subject, and drew up some short notes; these I enlarged in 1844 into a sketch of the conclusions which then seemed to me probable; from that period to the present day I have steadily pursued the same object. I hope that I may be See Zoologist for November, 1880.

excused for entering upon these personal details, as I give them to show that I have not been hasty in coming to a conclusion." "Origin of Species," p. 1, ed. 1859.

What could more completely throw us off the scent of the earlier evolutionists, or more distinctly imply that the whole theory of evolution that follows was an original growth in Mr. Darwin's own mind?

Mr. Romanes implies that I imagine Mr. Darwin to have "entered into a foul conspiracy with Dr. Krause, the editor of Kosmos," as against my book "Evolution, Old and New," and later on he supposes me to believe that I have discovered what he calls, in a style of English peculiar to our leading scientists, an 'erroneous conspiracy." The idea of any conspiracy at all never entered my mind, and there is not a word in “Unconscious Memory" which will warrant Mr. Romanes' imputation. man may make a cat's paw of another without entering into a conspiracy with him.

A

Later on Mr. Romanes says that I published "Evolution, Old and New," "in the hope of gaining some notoriety by deserving, and perhaps receiving, a contemptuous refutation from Mr. Darwin. I will not characterise this accusation in the terms which it merits.

I turn now to Dr. Krause's letter, and take its paragraphs in order.

1. Dr. Krause implies that the knowledge of what I was doing could have had nothing to do with Mr. Darwin's desire to bring out a translation of his (Dr. Krause's) essay, inasmuch as Mr. Darwin informed him of his desire to have the essay translated "more than two months prior to the publication of " my book, "Evolution, Old and New." This, I have no doubt, is true, but it does not make against the assumption which I made in "Unconscious Memory," for "Evolution, Old and New," was announced fully ten weeks before it was published. It was first announced on February 22, 1879, as about to contain 66 copious extracts " from the works of Dr. Erasmus Darwin and a comparison of his theory with that of his grandson, Mr. Charles Darwin. This announcement would show Mr. Darwin very plainly what my book was likely to contain ; but Dr. Krause does not say that Mr. Darwin wrote to him before February 22, 1879 -presumably because he cannot do so. I assumed that Mr. Darwin wrote somewhere about March 1, which would still be more than two months before" the publication of "Evolution, Old and New."

2. Dr. Krause says I assume that "Mr. Darwin had urged him to insert an underhand attack upon him (Mr. Butler).' I did not assume this; I did not believe it; I have not said anything that can be construed to this effect. I said that Dr. Krause's concluding sentence was an attack upon me; Dr. Krause admits this. I said that under the circumstances of Mr. Darwin's preface (which distinctly precluded the reader from believing that it could be meant for me) the attack was not an open, but a covert one; that it was spurious-not what through Mr. Darwin's preface it professed to be; that it was antedated; that it was therefore a spurious and covert attack upon an opponent interpolated into a revised edition, the revision of which had been concealed. This was what I said, but it is what neither Mr. Romanes nor Dr. Krause venture to deny. I neither thought nor implied that Mr. Darwin asked Dr. Krause to write the attack. This would not be at all in Mr. Darwin's manner.

3. Dr. Krause does not deny that he had my book before him when he was amending his article. He admits having taken a passage from it without acknowledgment. He calls a page and a half" a remark," I cali it "a passage." He says he did not take a second passage. I did not say he had; I only said the second passage was "presumably taken from my book, whereas the first "certainly was so. The presumption was strong, for the passage in question was not in Dr. Kranse's original article; it was in my book, which Dr. Krause admits to have had before him when amending his article, and it came out in the amended article; but if Dr. Krause says it is merely a coincidence, of course there is an end of the matter.

4. Dr. Krause, taking up the cudgels for Mr. Darwin, does not indeed deny the allegations I have made as to the covertness, and spuriousness, and antedating of the attack upon myself, but contends that "this is not due to design, but is simply the result of an oversight"; he is good enough to add that this oversight "could only be most agreeable" to myself. When I am not in the wrong I prefer my friends to keep as closely as they can to the facts, and to leave it to me to judge whether a modification of them would be "most agreeable to me or no. What, I wonder, does Dr. Krause mean by oversight? Does he mean

that Mr. Darwin did not know the conclusion of Dr. Krause's essay to be an attack upon myself? Dr. Krause says, "To every reader posted up in the subject this could not be doubtful," meaning, I suppose, that no one could doubt that I was the person aimed at. Does he mean to say Mr. Darwin did not know he was giving a revised article as an unrevised one? Does he mean that Mr. Darwin did not know he was saying what was not true when he said that my book appeared subsequently to what he was then giving to the public? Does he pretend that Mr. Darwin's case was not made apparently better and mine worse by the supposed oversight? If the contention of oversight is possible, surely Mr. Darwin would make it himself, and surely also he would have made it earlier? Granting for a moment that an author of Mr. Darwin's experience could be guilty of such an oversight, why did he not when it was first pointed out, more than twelve months since, take one of the many and easy means at his disposal of repairing in public the injury he had publicly inflicted? If he had done this he would have heard no more about the matter As it was, he evaded my gravamen, and the only step he even proposed to take was made contingent upon a reprint of his book being called for. As a matter of fact a reprint has not been called for. Mr. Darwin's only excuse for what he had done, in his letter to myself, was that it was "so common a practice" for an author to take an opportunity of revising his work that "it never occurred" to him to state that Dr. Krause's article had been modified. It is doubtless a common practice for authors to revise their work, but it is not common when an attack upon an opponent is known to have been interpolated into a revised edition the revision of which is concealed, to state with every circumstance of distinctness that the attack was published prior to the work which it attacked.

from me.

To conclude: I suppose Mr. Romanes will maintain me to be so unimportant a person that Mr. Darwin has no call to bear in mind the first principles of fair play where I am concerned, just as we need keep no faith with the lower animals. If Mr. Darwin chooses to take this ground, and does not mind going on selling a book which contains a grave inaccuracy, advantageous to himself and prejudicial to another writer, without taking any steps to correct it, he is welcome to do so as far as I am concernedhe hurts himself more than he hurts me. But there is another aspect of the matter to which I am less indifferent: I refer to its bearing upon the standard of good faith and gentlemanly conduct which should prevail among Englishmen—and perhaps among Germans too. I maintain that Mr. Darwin's recent action and that of those who, like Mr. Romanes, defend it, has a lowering effect upon this standard. S. BUTLER

Geological Climates

WHEN a reader of the intelligence of Mr. Wallace misunderstands my words it becomes plain to me they have failed to convey my meaning. I do not accept the interpretation he has put upon them, nor do I admit that even that interpretation would tell so much in favour of his theory as he supposes.

As however I agree with him that the question is far too large to be fully discussed in your columns, I shall allow the controversy, so far as I am concerned, to terminate, and shall publish my detailed views on geological climate in another SAMUEL HAUGHTON

way.

Trinity College, Dublin, January 27

On the Spectrum of Carbon

IN the discussions on the spectrum of carbon which have recently appeared in your journal much stress is laid on the impossibility of volatilising that substance by any heat which man can produce. I think this assumption is not warranted by experience. Two or three facts in Despretz' account of a remarkable set of experiments which he made about thirty years ago, seem to me to show it to be unfounded. This is given in the Comptes rendus, vol. xxviii. He exposed rods of anthracite to the action of 125 Bunsens (zines 5 in. high) and also to the solar focus of an annular lens 36 in. diameter. The rods bent under the combined action, and even appeared to fuse! In vol. xxix. he describes experiments with rods of sugar-charcoal under a battery of 500 similar cells. The electric egg was covered suddenly with a hard block crystalline powder.

He thinks attempts to fuse carbon should be made in condensed nitrogen and in metallic vessels. In the same volume he says that with 600 cells rods of sugar charcoal bend-swell at the

with great precision. The charts accompanying Sabine's "Contributions to Terrestrial Magnetism," No. ix. (Phil. Trans. 1849), were among the earliest on which the data whence the curves were drawn are recorded, although it may be observed that even a portion of the observations made at sea and utilised in these charts had no corrections applied to them for the effects of the ship's iron.

Considering the local magnetic disturbance found to exist on land in many regions and the large area of watercovered portions of the globe, observations made at sea, when systematically carried out and corrected for local attraction in the ship, have become an important factor in ascertaining the magnetic variation for the use of navigators at any given epoch.

Evans's Variation chart for the epoch 1858, embracing the navigable parts of the world, and in which the whole of the observations made at sea were corrected for the effects of the ship's iron, was published by the Admiralty. A further advance on Variation charts of an earlier date was the addition to this of a map showing the amount of annual change of the variation as determined at several localities, enabling reductions for the succeeding ten years to be made with a reasonable approach to the truth.

The increase of iron-built and composite vessels in late years has rendered a reliable Variation chart a necessary adjunct to navigation. This object appears to have been kept steadily in view by the Hydrographic Department of the Admiralty, for, in 1871, a new edition of the "Variation Chart of the World," reduced to that epoch (with polar charts added) was published in continuation of the chart for 1858. This chart was the result of the joint labours of Capt. Evans and a member of the compass department, Navigating-Lieut. Creak, R. N.

We have now to notice the more recent publications of these contributions to terrestrial magnetism. A chart of the curves for 1880, in continuation of those for the epochs 1858 and 1871, by Staff-Commander Creak, has been published by the Admiralty. In its construction the observations made during the voyage of H.M.S. Challenger (1872-76) have been introduced, and amongst results from other sources, specially those taken from Mr. A. Schott's papers on the secular change of the variation published as Appendix No. 8 to the U.S. Coast Survey Report for 1874, and also as a preliminary publication to the Report for 1879; Dr. Thorpe's observations in the United States, made about the 40th parallel of latitude, and results from the maps of the excellent magnetic survey of a large portion of the Eastern Archipelago in 1874-77, made by Dr. Rijckevorsel, have also been included.

As confined to special portions of the world a map of the United States for the epoch 1875, constructed by Mr. J. E. Hilgard, Assistant U.S. coast and geodetic surveys, published in the American Journal of Science for March, 1880, and illustrating an article on the subject of magnetic variation or declination, is of a high order of excellence.

In this map the curves, which show several flexures strictly pourtraying results arising from local disturbance, have been drawn for every degree of [equal] variation. The results are from observations made during the progress of the U.S. Coast Survey up to 1877, also from about 200 observations made in the interior of the country under the direction of Mr. Hilgard, to which were added every available observation from the land and boundary surveys, as well as those of private observers. Many of these results having been obtained at different periods of time, have been reduced to the given epoch by means of Mr. A. Schott's paper on Secular Change before referred to.

Although in maps and charts covering large geographical areas the variation lines for the land portions are generally drawn in regular curves (and so far deviating from strict accuracy), whilst those for the larger sea areas

are necessarily so done, still in delineating the magnetic features of a portion of a continent the system followed by Mr. Hilgard, as also by Lamont in his European surveys between 1850 and 1860, commends itself for accuracy.

The late Prof. A. D. Bache, who took a personal interest in the study of terrestrial magnetism, bequeathed a fund for scientific research. The expenses of obtaining the 200 observations in the interior of the United States before mentioned, were defrayed by a grant from this fund.

THE ZOOLOGICAL STATION AT NAPLES

WHAT is a zoological station?" is a question we have often heard asked when Dr. Dohrn's institution at Naples is under discussion. A "zoological station" (according to Dr. Dohrn), we may reply, is a kind of zoological garden for marine animals, or what is commonly called an "aquarium," only that, contrary to the usual practice at Brighton, Westminster, and elsewhere, the scientific element of the establishment is mostly cultivated instead of the popular branch. Such at least is the case under Dr. Dohrn's system, and also, we believe, in other zoological stations that have been formed after his example.

It must be recollected that the lower forms of organic life, to the study of which zoological stations, as thus described, are mainly devoted, are much more numerous than the vertebrata, and much less understood. Even in our own seas a vast amount remains to be done before our knowledge of the thousands of marine organisms which populate our waters and shores can be deemed to be anything like complete. Still more is this the case in the Mediterranean, where under a bright sky and burning sun the clear waters teem with animal life in all its varieties. It was no doubt the well-known productiveness of the coast of Naples and the facilities offered for dredging in its land-locked Bay that induced Dr. Dohrn to fix his "Zoological Station" in this quarter instead of planting it on the shores of his Fatherland.

After several years of incessant labour Dr. Dohrn has got his establishment into excellent working order, and, as will be seen by our advertisement pages, promises us after so much cultivation a rich and abundant harvest. The proper subject to take up when the publication of results was determined upon was obviously the Biology of the Bay of Naples. Great difficulties however beset the advance of this project. As regards the Fishes, the more highly-organised Crustaceans, the Mollusca, and some of the Cœlenterata and Echinodermata, it appeared possible for the students at the Zoological Station to avail themselves largely of the results arrived at by former workers. But when they proceeded to examine into the scattered literature in which the innumerable armies of Lower Crustaceans, Annelids, Nemertians, Planarians, Nematodes, and such-like creatures are described, the case was very different. The ancient naturalists have mostly characterised their species in these groups in such vague diagnoses that it is impossible to identify them. Under such circumstances the students of the higher animals are accustomed to resort to the type-specimens whence the descriptions were taken in order to see what the authors really intended. But the impossibility of preserving many of the lower animals cuts this resource away from the marine zoologists, who have consequently contented themselves in some instances with referring their specimens to species never sufficiently described, in other cases with describing them as new. Hence has arisen a mass of confusion which can be only regarded as parallel to what existed among the more highly-organised animals in the ante- Linnean period. The transformations undergone by many of the lower marine animals and the extraordinary sexual differences add