2 Allen on the Recognition of Geographical Forms. \ . January 



In the progress of descriptive zoology the quest for new species 

 and new genera became rampant. The distinction of imposing a 

 new name, to be followed by nobis or m//u\ led always to a search 

 for differences. It was natural, in such a scramble, that resem- 

 blances should be overlooked, and that the study of individual 

 variation should receive little attention. The synonyms that form 

 such an array in our modern systematic treatises on zoology attest 

 the result. 



But not all descriptive naturalists erred equally or in the same 

 way. There always have been, of course, both splitters and lum- 

 pers, the one class more or less at arms with the other, the one 

 holding the other more or less in contempt. But aside from this 

 individual diversity among naturalists there have been periodic 

 phases of change in the matter of excessive splitting and the re- 

 vel se, which may be likened to the oscillations of a pendulum. 

 This is especially true in respect to our own country, and notably 

 in regard to North American ornithology during the last half 

 century. Within this period there have been at least three well- 

 defined oscillations of the ornithological pendulum. The first, in 

 the direction of excessive subdivision, reached its culmination 

 about the year 1S70. A reverse oscillation immediately followed, 

 sweeping in character, and of strong and sudden impetus. It 

 gradually spent itself during the latter part of the following decade. 

 A third oscillation, in the direction of the first, feebly set in soon 

 after, and, slowly acquiring momentum, now seems to have 

 reached a degree of force that challenges candid consideration. 



In this connection a brief review of the progress of our science 

 during the last fifty years may not be out of place. 



Fifty years ago there were no large collections of birds, either 

 in public museums or in private cabinets, anywhere in America 

 About this time the Government instituted a series of transcon- 

 tinental surveys, extending in nearly joarallel lines across the con- 

 tinent from about the 90th meridian westward to the Pacific coast, 

 these lines being run at rather wide intervals from the Mexican 

 border on the south to the British boundary on the north. These 

 several military surveying parties were usually accompanied by 

 good field naturalists and collectors. Also at about the same time 

 the Smithsonian Institution, through the influence and direction 

 of the late Professor Baird, secured correspondents and collectors 

 at many points in British America. All of the collections thus 



