8 ANALYSIS OF THE TWO EDITIONS. 



97. Anser albifrons (verus). Greenland. 



98. Bernicla brenta nigricans. Recognized as a subspecies. 



99. Somateria moUissima dresseri. Recognized as a subspecies. 



100. Phaethon aethereus. Newfoundland. 



101. Phalacrocorax violaceus resplendens. Recognized as a subspecies. California. 



102. Larus cacliinnans. Alaska. 



103. Larus affinis. Greenland. 



104. Larus canus. Labrador. 



105. CEstrelata bul-weri. Greenland. 



106. Podicipes auritus (verus). Greenland. 



107. Brachyrhamphus brachypterus. Restored. Pacific Coast. 



108. Brachyrhamphus hypoleucus. California. 



109. Brachyrhamphus craverii. California. 



110. Lomvia troile californica. Recognized as a subspecies. California. 



The original number of names, 778, minus 10, plus 120, gives the total of 888 of 

 the present edition of the " Check List." The number seems large, in comparison, 

 and I am free to confess that it includes some — some twenty or thirty, perhaps — 

 which m}' conservatism would not have allowed me to describe as valid, and the 

 validity of which I can scarcely endorse. I have nevertheless admitted them to a 

 place, because I preferred, in preparing a " Check List" for general purposes, rather 

 to present the full number of names in current usage, and let them stand for what 

 they may be worth, than to exercise any right of private judgment, or make any 

 critical investigation of the merits of disputed cases. Probabl}', however, there are 

 not more than thirty cases of birds retained in this list whose claims to be recog- 

 nized by subspecific names can be seriously questioned. 



It should be observed, that the list is not yet to be regarded as finall}' filled. 

 Our southern border has proved so fruitful of Mexican species, that various others 

 doubtless remain to be there detected ; and several species described as Texan by 

 Giraud in 1841 remain to be confirmed. With the accessions that ma}' reasonably 

 be expected, and under current usage in the discrimination of subspecific forms, the 

 list will probably in a few years contain about 900 names of birds occurring in 

 North America north of Mexico and inclusive of Greenland. 



It is to be added here, that the present southern boundary of " North. America" 

 is a political one, wholly arbitrar}' so far as natural Faunal areas are concerned. It 

 would be far more satisfactory, from a scientific standpoint, to ignore the present 

 political line, and construct the '-North American" Ust upon consideration of the 

 limits of the " Nearctic Region " of Sclater and Baird. This would be to extend our 

 area along the table-lands and higher region of Mexico to about the Isthmus of 

 Tehuantepec, but not so far in the tierras calientes of either coast of that countr}^ : 

 on an average about to the Tropic of Cancer. Such course would give us the 

 natural instead of the political Ornis of our country ; and I have no doubt that it 

 will some day be taken. A few Cape St. Lucas birds have been so long in the 

 "North American" Hst, that it is not thought worth while to displace them; but 

 with these exceptions, it is not intended to include any species not known to occur 

 north of Mexico. 



