SCIENCE. 



141 



SCIENCE: 



A Weekly Record of Scientific 

 Progress. 



JOHN MICHELS, Editor. 



Published at 



229 BROADWAY, NEW YORK. 



P. O. Box 3838. 



SATURDAY, SEPTEMBER 18, 1880. 



Professor Alexander Agassiz's address, de- 

 livered in Saunders' Theatre, Cambridge, which we 

 print in full on another page, must be considered 

 one of the most important events of the great Bos- 

 ton meeting. 



In his position as Vice-President of the Biological 

 Section nothing could be more appropriate than 

 the expression of his views upon the direction 

 which modern biological research is taking. Ani- 

 mated by his own experience and convictions, his 

 address was a deliberate and able attack upon the 

 prevailing tendency towards too rapid generaliza- 

 tion — a tendency which has been increasing during 

 the last fifteen years, and is clearly the outgrowth 

 of the intense desire of modern biologists to break 

 down each and every barrier which obstructs our 

 view in the history of development. Natural and 

 laudable as is the desire to leave no stone unturned 

 in our knowledge of the relationships of the differ- 

 ent branches of the animal kingdom, it can only 

 result in the obstruction of future investigators if it 

 is not kept strictly within the limits of the truth. 

 Phylogenetic inquiries add greatly to the zest of 

 study, but should not be carried so far as to ham- 

 per or obscure the real end in view, which is, of 

 course, truth and precision of statement, with the 

 line sharply defined between what is actually seen 

 and that which it is inferred ought to be seen. 



Prof. Agassiz based his conclusions upon his 

 comprehensive study of the sea-urchin. Stating 

 as a premise the now well-known fact that in their 

 embyological development the modern forms repeat 

 the stages through which their ancestors passed in 

 fossil history, he carefully traced the parallelism in 

 a number of modern and fossil forms, giving an 

 outline of his recent study. The results have been 

 in all cases in positive confirmation of the above 

 premise, and show the very close affiliation of the 

 oldest and most recent forms, in general characters. 

 But while the sea-urchins, with a comparatively 



small number of existing species, and with a com- 

 paratively complete fossil record, offer a tempting 

 field for speculation, Prof. Agassiz denied his right 

 to group the genera into anything like a complete 

 genealogical tree. " If," he concluded, " when we 

 take one of the most limited groups of the animal 

 kingdom, we find ourselves engaged in a hopeless 

 task, what must be the prospect should we attack 

 the problem of other classes or groups of the ani- 

 mal kingdom, where the species run into thousands, 

 while they number only tens in the case we have 

 attempted to carry out? Shall we say ' ignora- 

 bimus' or ' impavidi progrediamus,' and valiantly 

 chase a phantom we can never hope to seize?" 



It was hardly to be expected that such an attack 

 as this would pass unnoticed, and in fact, one of 

 the features of the meetings of the Biological Sec- 

 tion was a debate growing out of it, which took 

 place on the following day. Prof. Cope had been 

 reading an able paper upon the succession of the 

 extinct Felidae, pointing to the modifications of the 

 teeth as a basis for forming a complete genetic 

 series. At the close of his paper he called Prof. 

 Agassiz's attention to the fact that here, in the cat 

 family, was an instance leading in quite an oppo- 

 site direction to that which Prof. Agassiz had 

 assumed in his address the day before. An inter- 

 esting discussion followed. Prof. Agassiz said he 

 did not object to the grouping of genera into lines 

 of descent where the structural characters were 

 sufficiently homologous, but he did object to regard- 

 ing such affinity as justifying the introduction of 

 hypothetical links into other parts of the chain, 

 and he did not see that the modifications of a single 

 character, the teeth, warranted the phylogenetic 

 conclusions which Prof. Cope had just reached. 

 Prof. Burt Wilder added that, in his own study upon 

 the pectoral muscles of the dog and other animals, 

 he had found the fallacy of hasty generalization 

 for genetic inferences, drawn from the muscles 

 alone, would widely differ from the facts of actual 

 relationship. Prof. Cope replied that in such 

 questions all must admit that different values should 

 be assigned to different parts of the animal frame, 

 and among the hard parts, of course, he ranked, 

 first, the limbs, then, he said, came the teeth. In 

 justification of his arrangement of the extinct cats 

 into two lines of descent from a common ancestor, 

 he said that the complication of the brains confirm- 

 ed the history told by the teeth. Prof. Agassiz em- 

 phatically repeated his statement of the day before 

 and the discussion closed. We hope this address 

 will be widely circulated and read ; if received in 

 the spirit in which Prof. Agassiz intended it, its 

 effect will be admirable. The reaction from the 

 theory of special creation is running strongly in 

 every quarter, and in a day when we find ingenious 

 speculations advanced even in small memoirs, 

 every one must admit the necessity of a more con- 

 servative spirit. There is no danger of going into 

 the old and opposite extreme, nor does Prof. Agas- 

 siz's address encourage the return movement. It is 

 a re-statement of the old piece of advice — do not 

 attempt to run before you are sure you can walk. 



