December 30, 1898.] 



SCIENCE. 



955 



amphibians. I have since sought diligently for 

 the ancestors of birds among the early reptiles, 

 with, I trust, some measure of success, but this 

 is a simple problem compared with the origin 

 of mammals which we liave before us to day. 



In various interviews with Francis Balfour, in 

 1881, at the York meeting of the British Asso- 

 ciation, we discussed the same questions, and 

 agreed that tlie solution could best be reached 

 by the aid of embryology and paleontology 

 combined. He offered to take up the young 

 stages of recent forms, and I agreed to study 

 the fossils for other evidence. His untimely 

 death, which occurred soon after, prevented 

 this promised investigation, and natural science 

 still suffers from his loss. Had Balfour lived 

 he might have given us to-day the solution of 

 the great question before us, and the present 

 discussion would have been unnecessary. 



The birds, like the mammals, have developed 

 - certain characters higher than those of reptiles, 

 and thus the two classes seem to approach each 

 other. I doubt, however, if they are connected 

 genetically, unless in a very remote way. 



Reptiles, although much lower in rank than 

 birds, resemble mammals in various ways, but 

 this may he only an adaptive likeness. Both 

 of these classes may be made up of complex 

 groups only distantly related. Having both 

 developed along similar lines, they exhibit va- 

 rious points of resemblance that may easily be 

 mistaken for indications of real aflBnity. 



In the amphibians, especially in the oldest 

 forms, there are hints of a true relationship 

 with both reptiles and mammals. It seems to 

 me, therefore, that in some of the minute primi- 

 tive forms, as old as the Devonian, if not still 

 more ancient, we may yet find the key to the 

 great mystery of the origin of mammals. 



O. C. Marsh. 



ZOOLOGICAL BIBLIOGRAPHY. 



To THE Editor op Science : I am glad to 

 see from Mr. Bather's letter in Science (No. 

 207) that the recommendations of the Committee 

 on zoological and botanical publications are not 

 what one would be justifled in inferring from 

 the printed abstract on which my remarks were 

 founded. All zoologists are under obligations 

 to Mr. Bather and his associates for their labors 



in the more arid, but not the less essential, 

 branches of the subject. We hope to be still 

 more grateful to them when their present task 

 is completed, and, therefore, avail ourselves 

 freely of the invitation to criticise the incom- 

 plete work in order that the completed struc- 

 ture may become more universally acceptable. 



Nevertheless, I find even in his new presenta- 

 tion of the subject a lingering trace of the as- 

 sumption that certain things are settled which 

 do not appear to me to be determinate. What 

 is the definition adopted by the committee of 

 the phrases 'distributed privately' and 'pub- 

 lished in the regular manner '? Upon this de- 

 pends whether all that follows may be accept- 

 able or not. How many is 'a few?' What is 

 'public' and what is 'private?' This sort of 

 thing should not be left doubtful. The answers 

 are by no means a matter of course. 



When an author, to avoid two or three years' 

 delay, pays for the prompt publication of his 

 researches he does not, in my experience, lock 

 up his copies in a safe and take his name out of 

 the Naturalist's Directory. On the contrary, he 

 at once distributes copies to the journals inter- 

 ested in his branch of science and to the experts 

 in his special line, and sends a copy to Fried- 

 lander for the Natura Novitates, where it is adver- 

 tised at a price. If he should omit the latter 

 (a most improbable suggestion), and the paper is 

 of interest, he will certainly be called on and 

 glad to furnish copies to those desiring them. 

 The author who does not desire publicity for 

 his work, and has no known address, in my 

 opinion is a myth. Why otherwise should he 

 print at all ? 



I quite agree that the paper must be made 

 available to those who wish to purchase it, but 

 I do not for a moment admit that this must be 

 solely through the Society in whose Proceedings 

 it sees the light. 



How about the highly genteel persons who 

 publish in editions de luxe of 100 copies ? Such 

 works are frequently far more inaccessible than 

 those separata distributed by authors. 



It seems to me that the committee would do 

 well to state in the fullest detail their ideas of 

 what constitutes publication and how this shall 

 be registered. 



My own opinion is that the sort of thing crit- 



