Recent Literature. 
169 
and to be subordinated in rank by a trinomial appellation.” In a foot- 
note the author adds : “It should not be inferred from our remarks in this 
connection that we find the use of trinomials inconvenient in practical 
application. On the contrary, no other method seems at all adequate to 
the proper discrimination between isolated and intergrading forms, and 
the difficulty in the cases above alluded to arises wholly from the want of 
sufficient material to decide the question of intergradation or the contrary.” 
In regard to the treatment of doubtful cases “ the greatest care has been 
taken,” and “ previous conclusions” have been “carefully reconsidered, 
with the aid of all the material accessible, including many specimens not 
previously in hand. This reconsideration of the subject has, in not a 
few cases, resulted in a reversal of former opinion, specimens from impor- 
tant localities not before represented often deciding the point one way or 
the other. Every form whose characteristics bear unmistakably the 
impress of climatic or local influences, gradually less marked toward the 
habitat of another form, with which it thus intergrades, and all forms 
which certainly intergrade, no matter how widely distinct the opposite 
extremes may appear ( e . g., Colap fes auratus , and C. mexicanus , and 
the different races of Passerella ), together with intergrading forms whose 
peculiarities are not explained by any known ‘law’ of variation, have 
been reduced to subspecific rank. On the other hand, where the difference 
between allied forms is slight, but at the same time apparently constant, 
and not necessarily coincident with a difference of habitat ( e.g ., certain 
small Thrushes and the various forms of Junco), specific rank is upheld. 
There are some forms which future investigation, based upon adequate 
material, may decide to be of different rank from that accorded them 
here. We cheerfully acknowledge our fallibility, but at the same time 
would say that we have endeavored to be as consistent as possible, giving 
the rank of each form as it appears in the light of our present knowledge, 
independent of previous conclusions” {op. tit., pp. 9, 10). That the 
revision here presented is impartially and conscientiously made there 
can Ijp no doubt, evidence of which is afforded by the cancelling of 4 
species and 6 varieties for the erection of which Mr. Ridgway is himself 
either wholly or in part responsible, while others for which Professor 
Baird stands sponsor share a similar fate. The really few changes in 
this respect from the status in Baird, Brewer, and Ridgway’s “ History 
of North American Birds” and Coues’s “ Check List” augurs well for a 
reasonable degree of fixity so far as forms now recognized are concerned. 
As already indicated, nomenclatural changes, simply as such, are nu- 
merous, affecting many generic as well as specific names. Very few of 
them are, however, now for the first time introduced ; quite a proportion 
have gradually gained currency during the last five years, but many of 
them date from April, 1880.* While quite a number of the long-familiar 
* See Coues, “ Notes and Queries concerning the Nomenclature of North American 
Birds,” Bull. Nutt. Orn. Club, V, pp. 95-102, April, 1880. Ridgway, “ Revisions of No- 
menclature of certain North American Birds,” Proc. U. S. Nat. Mus., 1880, pp. 1-16, 
“ March 27, 1880.” 
