PROCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 15 



The trinominals in Dall and Bauiiister's pajier on the Birds of Alaska 

 (Tr. Chicg. Acad. I, 18G9,) rest also evidently mainly on Professor 

 Baird's authority. 

 Buteo swainsoni var. insignatus. 

 Pyrrhula coccinea var. cassini Baird. 

 Pelidna alpina var. americana Cass. 

 Bern icla canadensis var. occidentalis Baird. 



But while thus most of the American ornithologists of that date had 

 their attention drawn to the establishment of varieties or local races, 

 one of them, Prof. J. A. Allen, looked at ihe other side, pointed out the 

 value of the species, and determined the difference between the species 

 and the subspecies. Although no trinominals are found iii his great 

 work " On the Mammals and Winter Birds of East Florida" (Bull. Mus. 

 Comp. Zool. II, No. 3, 1871, ])]). lGl-450), still that article promoted 

 trinominalism in America more than any before by treating the subspe- 

 cies as synonyms under the species, applying to the latter "the test of 

 intergradation." It is his great merit to have formulated this principle, 

 without which Sundevall's and Schlegel's idea would not have gained 

 so easy a victory in America. Subspecies are distinguishable forms 

 which intergrade, while species do not intergrade : Here was the clue 

 found, here the guidance to a methodical and consistent trinominalism. 

 Others have tried to define similar principles, involving them in obscure 

 theoretical and philosophical phrases, while he, a true and sound 

 " American," fixed the oul}' practical rule in a few and simple words. 



The effect of his work in promoting trinominalism is very patent in 

 the review of it written by Dr. Elliott Coues (American Naturalist,. 

 June, 1871, pp. 3Gl:-373), as shown by the following quotation (p. 371) : 

 " But we insist upon the advisability, iii the present stage of our scienccy 

 of recognizing geographical and some other differentiations hy iiame,'^ 

 and in the apj)ended foot-note he remarks: " Not necessarily a 'specific' 

 name, but some one additional word, with or without the sign ' var.,' 

 that shall stamp the form we wish to isignalize. Ferhaps this would be 

 a judicious middle course, most apjdicable to the present state of the 

 science." 



We have now in our sketch reached about the year 1871, This year 

 and the next following ones were marked by an unusual activity on the 

 side of our ornithologists; new countries were disclosed, and new mate- 

 rial was coming in rapidly, and the large series now accumulating in the 

 museums proved intergradation between many forms which had been 

 regarded as valid species. 



At this same time two great works on North American ornithology 

 were in preparation, Baird, Brewer, and Eidgway's " History of North 

 American Birds," and Dr. Elliott Coues's "Key." 



It is almost a matter of course that from what is said above trinom- 

 inals should become a prominent feature of both these works. The sys- 

 tematic application of trinominals to the whole North American ornis 



