78 TRANSACTIONS OF THE [ FEB. 23, 
fessor Baird was thus confronted at the beginning of his work 
with a chaos of names and meagre descriptions, the legacy of 
his predecessors. Even not a few of the species of Audubon 
and Bachman were based on specimens from unknown local- 
ities, not always correctly supposed to be North American. 
Leconte, DeKay, Say, Ord, Ratinesque, and Harlan, and various 
foreign authors, had each contributed to the list of nominal 
species, many of which will forever remain undeterminable, while 
others have been duly relegated to the limbos of synonymy. 
The work of separating the chaff from the wheat, the false from 
the true, was a perplexing task, an intricate riddle, which Baird 
attacked with wonderful acumen and success, leaving a com- 
paratively smooth and easy path for his successors. 
This was, however, the period of excessive subdivision, the 
smallest recognizable differences serving as the basis of specific 
separation. Baird, as was natural, influenced by the methods 
of his time, contributed his share to the list of synonyms; yet, 
considering the inadequateness of his material, his lapses were 
few, and more than atoned for by the accuracy and detail of his 
descriptions. If he failed to substantiate tangible differences 
between closely allied forms, it was because they did not exist, 
not from any lack of care in his work. Sometimes features of 
seasonal or individual variation were mistaken for specific dif- 
ference, but, as a rule, any forms recognized by Baird as species 
will bear the closest scrutiny, and are rarely found to be without 
some basis in nature—that is, if not “‘ good species,” they will be 
found to be what we now call geographical forms, or ‘‘subspecies.” 
The history of North American mammalogy and the history 
of North American ornithology run in closely parallel lines, the 
prominent workers being practically the same in each. In both 
of these departments there have been periods of excessive split- 
ting, followed by undue lumping. On a former occasion I have 
referred at length to ‘the oscillations of the ornithological pen- 
dulum”’ during the last thirty years.1_ In mammals, as in birds, 
a period of ‘‘lumping” set in about 1870, following along period 
during which the tendency had been to excessive subdivision, 
and extending into the present decade. The period from 1870 
to 1880 was thus not only a lumping period, but a transition 
period, and also one of unequalled activity. Work was carried 
on also from a basis in some respects the exact reverse from that 
of the immediately preceding epoch. While the outcome was on 
the whole a marked advance on what had preceded, it is ob- 
viously open to material revision as seen from the standpoint of 
1 The Auk, Vol. VII., Jan., 1890, pp. 1-9. 
