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Texas, to Honolulu were doing well and in- tion of a genus was not adopted; (6) it was creasing rapidly. When liberated they im- voted that after January 1, 1908, new names mediately began devouring the mosquito larvæ. should not be valid unless accompanied by The Mollienesia are viviparous and soon after Latin diagnoses. Unfortunately, no prelimthey were released many young were born. inary meetings of the committee had been held At the latest report the minnows numbered for discussion and perfection of the code, and about 2,000.

the proposals of the Americans to refer to The first regular paper of the evening was committees points to which there was a large by Dr. E. L. Greene on 'Linnæus as an Evolu- opposition was rejected. tionist. In the Philosophia Botanica' it Dr. Stiles discussed several points in conwas shown that Linnæus had clearly expressed nection with Mr. Coville's paper. He exhis views that species were the same as when plained the organization of the international created in the beginning and as they were to commission on zoological nomenclature and remain for all time. In the later 'Species expressed the opinion that such organization Plantarum’ Dr. Greene was interested to find was superior to the plan followed by the bota query as to whether a certain species were anists, as the zoological plan not only provides not derived from another related species, and for any necessary changes, but guards against on reading through the 1,600 pages of any radical and unnecessary changes in nothis work he found numerous queries as to menclatural customs. He thought that when whether one species of plant had not been zoological and botanical nomenclature were derived from some other species or acquired declared as independent of each other a very certain characters by adaptation to environ- unfortunate mistake was committed, since ment-soil or climatic conditions. Thus such a rule was made without consideration while in one place expressing an orthodox of the numerous difficulties it would make for belief in special creation, his later querying is men working in the protozoa. However, now that of an advanced and pronounced evolu- that the rule was generally adopted it was not tionist.

feasible to attempt to rescind the rule. The The second paper on the program was by Mr. zoological code provided, however, for certain Frederick V. Coville, on The International cases which arise. He was of the opinion Botanical Congress at Vienna.' He said this that the botanical provision that all new dewas one of a series held every five years. It scriptions should be written in Latin was an was attended by about 500 delegates, from the unfortunate one and not capable of general United States and most European countries, practical application. He maintained that of which the German-Austrian group was any man is able to write his own mother greatly in the majority. The morning ses- tongue more clearly and more concisely than sions of the meetings were devoted to presen- he is able to express himself in a foreign tation of botanical papers, the afternoon ses- language; further, probably not fifty per cent. sions to the adoption of a code of botanical of the men actively engaged in zoological and nomenclature. The main questions brought botanical work are able to read Latin with up were: (1) The rejection of the Kew rule ease and certainly a smaller per cent. are able by adopting the principle of retaining the to write Latin. The rule in question as oldest specific name in whatever genus pub- adopted by the botanists seemed to him not lished; (2) an exception to the retention of only a step backwards but further it played the oldest specific name was made when it into a rather important local question in eduwas identical with the name of the genus; cational matters in certain countries and the (3) the American principle of rejecting ho- rule would doubtless be cited by scientists in monyms was not adopted; (4) the principle those countries. in support of certain questions of fixing upon a single species as the type of and legislation which were of purely local a genus was not accepted; (5) the principle interest to those countries. It would further of binomialism as a requisite for the publica- result in decreasing the activity of a number

of men in scientific work in case an attempt were made to enforce the rule. He believed, however, that the rule would be ignored by the majority of workers. Regarding the principle of tautonomy, he expressed himself not only as not opposed to it but as highly in favor of it, and he himself has decided to purposely introduce tautonimic names whenever the occasion presents itself. By use of tautonomy, the type species of a genus is shown in its name; without tautonomy, it is necessary to refer to the literature in order to recall the type species.

He did not believe it possible to enforce the rule concerning the list of excepted names. In fact, this rule did not seem to mean very much to him, as the congress had failed to determine the types for the names which were excepted and had apparently failed to provide for cases in which the genera in question might be defined in the future.

He recognized the delicacy of the situation which now faces the American botanists, but it seemed to him that the botanical code contained so many subjective elements that it was impossible for this code to expect to have a very long life. It has been the history of nomenclature since the time of Linnaeus that rules based on subjective ideas were shortlived. A rule in nomenclature must be objective if we expect it to be accepted generally and if we expect it to be permanent. Discussion followed by Dr. Gill.

The last paper on the program was by Dr. Hugh M. Smith on the "Sargassum Fish,' a tropical species of the southern Atlantic occasionally brought by winds and currents to more northern shores. A large number of the fish were taken at Woods Holl and vicinity. The eggs from these prove to be entirely different from those described by Agassiz and long supposed to have belonged to the sargassum fish. Specimens of the fish were shown and a beautiful painting of it by C. R. Knight, showing its wonderful protective coloration. The paper was discussed by Dr. Gill.

DISCUSSION AND CORRESPONDENCE.
ONTOGENETIC SPECIES AND OTHER SPECIES.

REFERRING to the admirable article in SciENCE (November 24, 1905, p. 661) on 'The Evolution of Species through Climatic Conditions,' by Dr. J. A. Allen, I may once more gratefully recognize my own especial indebtedness to Dr. Allen's pioneer investigations of thirty years ago in this particular direction. These studies have been epoch-making in the history of ornithology.

It remains, however, to be determined whether these environmental forms—these species and subspecies produced by the direct influence of heat, cold, humidity and aridity ---are ‘ontogenetic species' (a term originating, so far as I know, with Professor V. L. Kellogg) or whether they have a real existence outside the lifetime of the individuals actually composing the group or species. We do not know which of the traits induced by direct section of the environment, if any, are actually hereditary and which are not. If we find that the dusky woodpeckers of Vancouver Island retain this shade when reared in Arizona, then humidity would be a real factor in the formation of species. If such birds, transferred in the egg to a new region should develop in the fashion of the local race of this region, and not like their own parents, then the duskiness is not a true specific or subspecific character. The real character of the species would be found in the tendency to develop dark plumage in humid surroundings and pale feathers under other conditions. In such case humidity would be merely a factor modifying individual development but not connected with the origin of species.

It may be that these questions have been already solved by experiment on birds, but if so, the experiments have escaped my attention. Eggs of the woodpeckers, chickadees and other birds showing dusky phases should be hatched in the arid plains. The red-shafted flicker of California should be bred in New England, and the permanence of the difference between large birds of northern range and their smaller southern homologues should be tested.

VERNON BAILEY, Recording Secretary, pro tem.

Difference of external conditions is not necessary to diversity of evolution.

Separation and variation—that is, variation not

separation and overwhelmed by crossing-is all that is necessary to secure divergence of type in the descendants of one stock, though external conditions remain the same and though the separation is other than geological. The separation I speak of is anything in the species or the environment that divides the species into two or more sections that do not freely intercross, whether the different sections remain in the original home or enter new and dissimilar environments.

All of this is in general accord with my own experience.

DAVID STARR JORDAN.

An'ontogenetic species' its traits produced by the direct action of the environment, is the Loch Leven trout (Salmo levenensis '), which I have lately discussed in these columns. Transferred to the brooks of England or to those of California, this supposed species loses its lake-bred characters and becomes the common brook trout.

Perhaps our ornithologists will some day test their species and subspecies by a test of the permanence of this class of characters. No doubt we should drop from the systematic lists all forms which may prove to be purely ontogenetic, all whose traits are not fixed in heredity.

In my recent article, as noticed by Dr. Allen, I have used the word 'barrier' a little too vaguely. For the purposes of this study, I should regard a broad plain as a barrier to a species which inhabits it, even though it were abundant, from one side to the other. A barrier in this sense is anything whatever which checks free interbreeding, even though it offers no actual check to the life or movement of the species. With quiescent animals, the individual moves but a short distance and the traits at one end of an unbroken series may be quite different from those of other individuals at the farther end, as Dr. Allen has very properly suggested. The term 'bionomic barrier,' used by Dr. A. E. Ortmann in a personal letter, seems to me a very apt one as covering the species-producing phases of isolation.

Certain papers of Rev. John T. Gulick on the evolution of species of land-snails and other animals deserve more attention than they have received. In one of these papers, 'Divergent Evolution through Cumulative Segregation' (Smithsonian Report for 1891, p. 273), Mr. Gulick corrects certain erroneous assumptions on the part of Dr. Moritz Wagner. Mr. Gulick says:

Separate generation is a necessary condition for divergent evolution but not for the transformation of all the survivors of a species in one way.

Separation does not necessarily imply any external barriers or even the occupation of separate districts.

Diversity of natural selection is not necessary to diversity of evolution.

ORTHOGENETIC VARIATION ? In a recent paper" I reviewed Gadow's hypothesis of Orthogenetic Variation," in the light of his own evidence, and in the light of such observations as could be added. In SCIENCE for November 7, 1905, Dr. Gadow publishes a reply under the title 'Orthogenetic Variation. It would be superfluous merely to rediscuss the data previously published; in fact, had the matter gone no further than the original paper, elaborate criticism in the first instance might have been unnecessary, since scientific readers could judge the evidence for themselves. But unfortunately, as will be shown below, subsequent use has been made of the idea for presentation to the general public, not expressly as a tentative hypothesis -but without qualification.

In the first paragraph of his reply, Gadow says, I am anxious that it [orthogenetic variation) should not be misrepresented,' and, in the second paragraph, the paper by Mr. Robert E. Coker * * * calls for some remarks on my part by way of protest and correction.' I was glad that after careful reading of his paper, I found no reference to any statement

? Gadow's hypothesis of 'Orthogenetic Variation in the shells of Chelonia,' Johns Hopkins University Circular, No. 178, May, 1905.

2 « Zoological Results Based on Material from New Britain, New Guinea, Loyalty Islands and elsewhere, collected during the years 1895, 1896 and 1897, by Arthur Willey,' Part III., pp. 207-222, Pl. XXIV., XXV., Camb. Univ. Press, May, 1899.

of mine that had 'misrepresented' his hy in both second and third groups; the two 24pothesis, and so needed correction. In fact, inch specimens in both third and fourth I did not suppose I could have misrepresented groups; and the seven large' specimens in it, because I had given it merely by quoting both fourth and fifth groups. Twenty-nine his own words at length. Two of the para- specimens divided into four groups, from graphs quoted by me Gadow quotes in his which a series of per cents. is computed to. recent paper, following them with the words be compared with a per cent. based on a com“I think I had stated the case fairly. It left paratively few newborn turtles—and this the no doubt about the definition of at least one sole basis for an elaborate hypothesis, given kind of orthogenetic variation” (p. 638). But to the scientific world with the supporting (?) we are indebted to his recent paper for the evidence and, subsequently, given to the genvery concise statement that cases of ortho- eral public, without the evidence, in a comgenetic variation are simply ontogenetic prehensive monograph on ‘Amphibia and stages, passing reminiscences of earlier phylo- Reptiles. This I regard as the sole basis,' genetic conditions. The basis for his assump- for though his comparison of the abnormalition that the abnormalities in number and ties with supposed phylogenetic stages is inarrangement of the horny shields of turtles teresting and suggestive, and may support an are 'orthogentic variations' is a table of per- interpretation of the abnormalities as atacentages of abnormalities, made from 76 speci- risms, it does not in the least imply that the mens (47 new-born, and 29 of various sizes, individual recapitulates these stages, and if from three inches to 'large'). This series of the latter assumption has other basis than the percentages of abnormalities, the percentage table of percentages, what is it? decreasing with age, is supposed to indicate The writer is now pursuing anatomical and that turtles 'amend their scutes' and 'grow embryological studies, the results of which out of these irregularities by the reduction or may have some bearing on the interpretation squeezing out of certain scutes.'

of the abnormalities in question, and these Gadow states (p. 639) that with the addi- results will be given out in due time. But tion of my embryos to his 76 specimens, 'the the question at present is not-Can Gadow's percentage still decreases with age’; and gives assumption be disproved? but-Have there the following revised table, including both been in hand facts to justify its promulgasets of turtles:

tion? Being promulgated, should it be in

Cortcluded without qualification in a compreOf 733 embryos or newborn, 53 are abnormal.. 74 hensive monograph intended for the general Of 9 specimens from 3 to 8 inches, 3 are ab public, who will not refer to the original normal ............... .............. 33

paper to find that it is merely a hypothetical Of 19 specimens from 8 to 24 inches, 5 are ab.

assumption from a very small number of normal .................... ........... 225

facts? The reference is to the Cambridge Of 9 specimens from 24 inches to large,' 2 are · abnormal ................

Natural History,' Vol. VIII., “Amphibia and Of 7 large specimens, only 1 abnormal....... 127 Reptiles,' by Ilans Gadow (London, 1901),

where the following unqualified statements The table requires a comment. The last occur (the italics are mine): four groups are based, not on (9 +19+9+7) It is absolutely certain that the number of 44 specimens, but on only 29, for 15 turtles transverse rows also was originally much greater were counted twice: the six 8-inch specimens than it is now. The mode of reduction of the

3 Presumably typographical error. Gadow's 47 numbers of the neural and costal shields has been newborn plus my 28 embryos = 75.

studied in Thalassochelys caretta (cf. p. 388.) + Presumably typographical error. 70 intended. The accompanying illustration (Fig. 68) [This is • Presumably typographical error. 26 intended. a reproduction of text figure, from Willey's Zoo* Presumably typographical error. 22 intended. logical Results. R. E. C.] shows some of the many ? Presumably typographical error. 14 intended. stages actually obserred in the reduction of the

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shields. The chief point is that certain shields are squeezed out, or suppresscd by their enlarging neighbors. The ultimate result is the formation of fewer but larger shields.s

Can these words be intended figuratively, the reference being to phylogenetic development, not to 'orthogenetic variation,' with all that that term, as defined by Gadow, implies? If so, the cross reference on a later page is certainly misleading: for in his discussion of the variations of Thalassochelys caretta, he says:

The interesting fact in connection with these variations is, moreover, that some of the shields are much smaller than the others, sometimes mere vestiges in all stages of gradual suppression, and that the abnormalities are much more common in babies and small specimens than in adults. The importance of these 'orthogenetic variations' has been discussed on p. 326."

ROBERT E. COKER. Joins Hopkins UNIVERSITY,

November 28, 1905.

ON THE GRANTING OF THE M.D. DEGREE. A SHORT time ago I received a letter from a member of a state board of medical examiners which touches upon a matter of present interest.

The letter, from which I shall quote, was in reply to one giving information respecting courses in this college designed for students who have the study of medicine in view.

After remarking that in his state the medical examiners had decided to give one year's credit to graduates of colleges, provided cer tain subjects in biology, chemistry and physics had been pursued in the college course, he proceeds as follows:

The fact is that many of the colleges teach these branches better than the average medical school. Any ordinary high school boy can enter the medical department of the university. Yet, they are not willing to give a year's credit to men who take four years beyond their entrance requirement. The confederation of state medical boards is divided on the question. So long as the average medical school admits high school graduates, I shall stand for giving one year's time to men who

8 Loc. cit., p. 326. "Loc. cit., p. 388.

take a college course. Or, in other words, seven years for the combined medical and college course. Not six years as proposed by Michigan, provided men take both courses at Ann Arbor. The seven years seem to me to be only fair play as an encouragement to the higher education.

What I wish to write you about in particular, is this: The present regulation is not to give the college men any time credit. The plan originates with medical schools in universities where they have also an arts department. They do allow the medical and college course to be completed in six years instead of eight, but it requires men to go to their college department. Now there are several medical schools requiring a straight B.S. or A.B. degree for entrance, such as Johns Hopkins, Harvard, and Rush in 1907. If men going from colleges * * * will all go to schools requiring the A.B. or B.S. entrance requirement, it will do more to help us to bring the medical schools into line than anything I know of at present. It seems to me the professors in these colleges should bring every pressure to bear on their prospective medical students to get them to go to the medical schools only that require degrees for entrance.

Upon the question of requiring either the B.A. or the B.S. degree as a preliminary to a medical course it is not my purpose to speak further than to say that I do not think the time has come in this country to make such requirement, unless upon the completion of such course the degree M.D. is to be given.

President Hadley has this to say on the general subject of requirements for admission to the professional schools of Yale:

However convenient it might be to insist on the possession of a bachelor's degree by all pupils in the schools of law or medicine, I feel that it would be a violation of our duty to these professions to hedge ourselves about by any such artificial limitations. We should make the standard of admission to our law and medical schools higher than it is at present; but we should base it upon qualifications for professional study which we could test by an examination, rather than upon previous residence at an institution entitled to give a bachelor's degree. If a man is really fit to study law or medicine we should encourage him to study law or medicine with us, without making arbitrary restrictions.

No one will be likely to question the wisdom of President IIadley's remarks, provided the

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