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sequence, I propose to treat them both as comprehended in 
the genus Buteo, that genus being one which consists of an 
ageregation of several natural subgeneric groups, easy to per- 
ceive in studying the genus, though difficult to define by any 
characters save such as chiefly rest on peculiarities of colo- 
ration and markings at different ages. 
Mr. Ridgway, in an able paper to which allusion has already 
been made in an editorial notice in ‘The Ibis’ for 1875, 
p- 500, proposes that the genus Crazirex should be used to in- 
clude all those Buzzards which have “ only three of the outer 
primaries emarginated on their inner webs ;” but I fear that 
this is scarcely a character which can be satisfactorily used as 
a basis of generic or subgeneric distinction, inasmuch as it oc- 
casionally happens that the outline of the fourth primary varies 
somewhat as to the degree in which it 1s emarginated, or sin- 
uated, in different individuals of the same species; and this is 
especially the case in Buteo erythronotus, in which most of the 
specimens which I have examined have had the fourth primary 
distinctly emarginated, though I have seen two examples in 
which the emargination was barely visible; and’ the latter 
seems to have been the case with the specimens examined by 
Mr. Ridgway, since he includes this species amongst those 
which have but three emarginated. primaries, as he also does 
B. poliosomus, of which I have never examined a specimen 
with Jess than four primaries distinctly emarginated. 
In considering the genus Buteo in the extended sense to 
which I have just alluded, I propose to commence by refer- 
ring to B. erythronotus, and to those species which appear to 
me to be its nearest allies. 
Mr. Sharpe gives the length of the wing in the female of 
B. erythronotus as 18°5 inches, which I think must be a mis- 
print, as in the largest female that I have measured the length 
from the carpal joint to the tip of the wing is only 16°5. 
_ From an examination of the series of specimens of this 
Buzzard in the Norwich Museum, I am led to believe that 
the male bird passes through three distinct phases of plumage, 
the first being that which is described by Mr. Sharpe as 
“young,” and which is common to both sexes, the second 
