Margarita Island, Venezuela. 555 
in B. striata, but are more dusky brown. The sides of the 
face in the Margarita bird are dull slaty-brown, as are also 
the feathers of the neck. 
The immature bird has the sides of the face rufous, which 
is characteristic rather of B. virescens, so that it would 
appear that B. robinsont holds an intermediate position 
between B. striata and B. virescens. 
An immature bird which I shot in the Laguna del Obispo, 
on the northern coast of Venezuela, opposite Margarita, 
appears to be B. robinsoni rather than B. striata, while a 
specimen which I shot in Trinidad is undoubtedly B. striata. 
A bird which I obtained on Blanquilla Island tends towards 
B. virescens, but has points in which it resembles B. striata. 
Evidently, therefore, in the islands along these shores 
the ranges of the two species overlap and the two forms 
interbreed. 
Since writing the above, I notice that Mr. Hellmayr 
(“ Birds of Trinidad,’ Noy. Zool. xviii. no. 1, 1906, 
p- 51) states, under the heading Butorides virescens :—“ As 
far as I know, this species has not been taken before on the 
island of Trinidad; but since Mr. André sent only young 
birds I cannot determine to which of the numerous sub- 
species they should be referred.” He also states that a 
good series from Tobago appear to be true B. virescens, which 
helps to bear out the statement that the two forms tend to 
overlap and possibly interbreed along the northern coast of 
Venezuela. 
CATHARTES AURA. 
Cathartes aura Robinson, Proc. U.S. Nat. Mus. xvit. 
p. 661 (1895); Sharpe, Hand-l, B. i. p. 240 (1899) ; Clark, 
Auk, xix. p. 261 (1902). 
One adult. Jan. 6, 1904. [P. i. L.| 
The following note on the colour of the soft parts I took, 
with the help of Dr. Bowdler Sharpe, immediately I had 
shot this bird :— 
« Bill whitish; cere and fore part of head fleshy pink, 
with scanty black hairs all over the head and small tufts in 
