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there Megacerops,' by R. S. Lull, accompanied by an illustration which differs from others previously made in showing the animal with a short, double nasal horn. This, it is argued, was, like that of the rhinoceros, composed of agglutinated hairs. We have another of the • Synopses of North American Invertebrates,' this, No. XXI., by W. R. Coe, being devoted to the Nemerteans, part I. W. B. Davis gives the sixth paper on 'Studies of the Plant Cell, and the balance of the number is devoted to reviews and correspondence.
The American Museum Journal for July is termed the Reptile Number, the major part of its contents consisting of a synopsis of • The Reptiles of the Vicinity of New York City,' by Raymond L. Ditmars, accompanied by a key and numerous excellent illustrations. The article is issued separately as Guide Leaflet No. 19.
The Zoological Society Bulletin for July is as good as its predecessors. C. William Beebe describes ‘The New Bird House' at length, giving a number of fine illustrations of the building and its contents. There is an excellent article on ‘Labeling Live Animals' with samples of the labels used at the New York Zoological Park, one on" Tree Planting at the Zoological Park' and another on Our Series of Batrachians. The illustrations are particularly good.
who 'succeed’ in science. In SCIENCE of July 7, p. 27, are some fresh remarks on this subject, from the address of President Roosevelt to the alumni of Harvard. The time has come when the worm, with the kind permission of the editor, desires to turn.
I write as an ordinary working naturalist, and on behalf of my kind. We neither expect scintillating success,' nor do we look forward to any prizes in the way of highlypaid positions. Our needs are mainly two: (1) adequate time for work and (2) a living wage. These are exactly the things we can not have, in the present state of this country. It is only necessary to make a few inquiries among scientific workers, to find out that very few, even among the most distinguished, can pursue their studies unhindered. A very short time ago I had a conversation with one of the most able naturalists America has ever produced, holding an apparently excellent position, and he explained to me how he was obliged to spend a large part of his time in routine work, because of the lack of adequate assistance. A day or two later I talked to a man who has a most intimate knowledge of a certain group of animals, and has discovered many new facts; but few of his discoveries will ever be put in print, because of the incessant pressure of other duties. These men are not part of the 'great unemployed'; they hold positions most people would envy; and, moreover, they are excellent samples of all the rest.
The difficulty is intimately connected with the other one, that of the living wage. There is no is no living wage for research; research in pure science is at present a parasitic industry, to borrow a term from the economists. Both of the men I have just referred to get their salaries for doing economic work, and whatever they do in pure science is supported and made possible by the other. A still larger body of researchers lives upon the proceeds of teaching, while those who actually get a living by research are very, very few. The experiment stations, even, do not disobey the general rule, for the demand for immediate results of economic value is such that the workers are almost' obliged, in the majority of cases, to desist from work of a broad and fundamental
The Museums Journal of Great Britain for July completes the fourth volume of this valuable publication and includes the index. Its leading articles are “The New Local Museum in Bad Bielohrad, near Jitschin, Bohemia,' by Anton Fritsch, and “A System for the Registration of the Contents of Museums,' by L. Wray, of the Perak Museum. The interest and value of the Journal, however, lie largely in its numerous brief notes relating to many museums.
DISCUSSION AND CORRESPONDENCE.
THE NEEDS OF SCIENTIFIC MEN. Mrch has been said recently about the desirability of offering “brilliant prizes' to men
character; while most of them, of course, have J. O. Westwood, in his last years, ‘he never to do a large amount of teaching.
gets tired.' It would be difficult or impossible to over
T. D. A. COCKERELL. estimate the value of the teaching and economic work referred to. They are indispen THE EDITORSHIP OF THE ENGINEERING AND sable and in every way worthy of the support
MINING JOURNAL. they receive. But research in pure science TO THE EDITOR OF SCIENCE: On July 1, 1905, meaning by this term research directed toward Mr. T. A. Rickard relinquished the managing ascertaining the methods of nature without editorship of the Engineering and Mining immediate economic or educational ends-is Journal, a position which he held with merit even more necessary, for it is the rock on for two and a half years. Although Mr. which the other two must necessarily build. Rickard has been succeeded by others who will It also must be supported—and by whom? maintain the high standing of the Journal as Surely by the recipient of the benefits it con- a technical magazine, his voluntary retirefers, that is, the human race.
ment, in my opinion as an American geologist, I can not agree with President Roosevelt is a distinct loss to science in this country, that the highest work will never be affected
inasmuch as, in addition to his intimate by the question of compensation. It will be knowledge of the business side of mining, he and is continually affected by the fact that it appreciated the important relation of this subcan not get even the wherewithal to keep the ject to geology. Through this appreciation, machine at work. On the other hand, it is during his editorial encumbency, he secured likely to be totally destroyed, if affected at all, and stimulated many excellent original conby the offer of 'brilliant positions. For whattributions upon the geology of interesting are these positions, judging from those now localities, which would not otherwise have existing? Mainly and often wholly execu- been published. tive; useful and honorable, indeed, but not, Of all the economic applications of geology, in their essence, scientific positions at all!
the questions pertaining to the origin, occurWho proposes to pay a man ten thousand a
rence and availability of ore deposits are by year, and then leave him alone to go on with
far the most important, and, perhaps, the his work? Really, the situation suggests a
sympathy and encouragement of mining men slang expression, not fitted for the pages of
have been the greatest impetus in this country SCIENCE.
toward securing the means of purely scientific I once heard of an Englishman who said
research. he would work hard in science until he got
The numbers of the Journal edited by Mr. his F.R.S., and would then stop. We do not
Rickard constitute a most valuable addition want men with that spirit, who begin and
to the annals of American geology, and it is continue with the hope and expectation of a
hoped that the talents of business integrity, prize, financial or social. The scientific man
high idealism and charming literary style, so has his real prizes, which he values highly
rarely found in combination with scientific and of which he can not be robbed; these are
knowledge and so well developed in him, will to see his ideas and discoveries woven into the
not long continue idle. fabric of human knowledge, and become in
That Mr. Rickard has recently declined a tegral and essential parts of the great temple
professorship of mining in the Royal School of which he is one of the myriad builders.
of Mines, a position which carries with it title This alone is to him worth while; and it is a
and honor, and has chosen to remain in positive injury to divert him with baubles.
America, will be gratifying to all of his conHis prayer is, to be permitted to work as long
frères in the geological profession. as life lasts, and that it may be said of him, as I heard it said of that fine old entomologist,
R. T. II.
SPECIAL ARTICLES. A FOOTNOTE TO THE ANCESTRAL HISTORY OF THE
VERTEBRATE BRAIN. The existence of a pair of newly recognized ganglionated nerves, attached to the fore-brain of that ancient group of fishes—the Selachians
is. perhaps. of sufficient general interest to justify a brief mention in SCIENCE.
In recent numbers of the Anatomischer Anzeiger (Vol. XXVI., Nos. 2/3 and 4/5) the writer has described and illustrated the morphology of such nerves in twenty genera, and twenty-seven species, of selachians, and their embryonic history in one. Similar nerves have also been pointed out by Allis, Pinkus and Sewertzoff in two of the Dipnoi (Protopterus and Ceratodus), and one ganoid (Amia). So far as observations go these nerves are absent in all other vertebrates. The facts now made known, although in one sense merely anatomical details, may, nevertheless, be looked on as constituting a footnote to the great chapter in morphological science dealing with the structure and development of the vertebrate brain.
The fore-brain is extremely modified in structure, and so little understood that it is desirable to gain any new facts bearing on its organization. So far, comparative anatomy and embryology combined have supplied only fragmentary views as to its nature, the number of segments that may enter into it (or, indeed, whether it is segmented at all), and as to its line of development. Although the solution of these matters is likely to take many more generations, yet, in the meantime, de‘tails of structure hitherto unknown may help, be it ever so little, in the anatomical analysis of that region of the brain.
The new nerves referred to above exist in adult stages of selachians. They are, on the one hand, connected with the fore-brain and, on the other, with the olfactory epithelium. They arise earlier in embryonic history than the olfactory nerves, appearing on the anterior summit of the fore-brain near the neuropore. Peripherally they intermingle with the olfactory fibers, but, at all stages of their existence, they are entirely independent of those fibers, and they never come into rela
Fig. 1. Brain of Squatina angelus, from above, natural size.
emerges from the dorsal surface of the midbrain, while its neuroblasts lie in the ventral zone.
As an illustration of the first type, reference may be made to Figs. 1 and 2 showing, respectively, the brain of the angel-fish (Squatina angelus) and that of the spiny dog-fish (Squalus acanthias), one of our commonest selachians.
In Fig. 1 the new nerve (n. nov.) is seen attached by two roots to the dorsal surface of the prosencephalon, and, bearing just in front of the brain, a filiform ganglion (gn.). From this point it runs like a delicate thread along the olfactory tract, and dips into a fissure separating the two great divisions of
The microscopic structure of the ganglion, shown in Fig. 3, resembles that of a spinal ganglion. It is surrounded by a covering of connective tissue from which supporting strands pass into the interior of the ganglion. The ganglion-cells are arranged in clusters and layers between the nerve fibers and connective tissue elements. The nerve-cells are for the . most part bipolar (gn. cl.), but a limited number of other ganglion cells (gn. cl.'), with angular outlines and several processes leading from them, may also be seen, which suggest the presence of multipolar cells.
...... gn. cl.
The central terminations and peripheral distribution of the new nerve are shown in Fig. 4. This is partly diagrammatic, being based on a section in the horizontal plane of the brain of a Squalus acanthias about six inches long. Centrally, the nerve fibers enter the brain substance, and after much branching are distributed mainly within an eminence upon a median infolding of the pallium. This eminence is supposed to correspond to that designated' eminentia septalis ' by von Kupffer in the amphibian brain.
The study of serial sections shows that the fibers of the chief branches of the nerve are distributed, peripherally, to the olfactory membrane, in the antero-lateral portion of the olfactory cup. There are also some smaller
FIG. 3. Section of the ganglion of the new nerve of Squalus acanthias, Xoc. 2, obj. 2/3 in.
As an illustration of the other type, having a ventral attachment with the brain, we may take the brain of the common smooth hound (Mustelus canis) of the Atlantic coast, which is shown in Fig. 5. Here, the nerve emerges from (or enters) the brain substance on the ventral surface, about midway between the anterior border of the prosencephalon and the optic chiasma. It is interesting to note that, in embryonic development, it first arises upon the dorsal part of the primary fore-brain and is carried to its ventral position through the unequal growth of the brain-wall. The nerve penetrates the brain substance, and, after branching, terminates in the same region as in the brain of Squalus acanthias.
As shown in the figure, the nerve has two ganglia-a distal and a proximal one—as is the case with the ninth nerve. The peripheral distribution of the fibers is similar to that in Squalus acanthias.
A few comments in reference to this nerve may not be out of place. The only similar nerve known outside the group of selachians is in Amia, Protopterus and Ceratodus. In the two former genera no ganglion was observed by either Allis or Pinkus, but Sewertzoff, in 1902, noted a ganglion on this nerve in embryonic stages of Ceratodus. The ventral position of the nerve, close to the recessus præopticus in the three forms mentioned, led Sewertzoff to propose for it the name of 'Nervus præopticus,' but its dorsal position in so many selachians would make that name inappropriate. Earlier (1899) I had suggested in a tentative way the name 'accessory olfactory,' which is also objectional, as it prejudices the question of its function. Since this nerve arises on the morphological tip of the primary fore-brain, and during some stage of its existence is closely connected with the lamina terminalis, I think the designation 'Nervus terminalis' will fit all cases and will be a suitable name for it.
Both its anatomy and embryology, as given in my paper in the Anatomischer Anzeiger, bring out its marked individuality and separateness from other cranial nerves. This would justify calling it a 'new nerve' and, therefore, giving it a new name.