130 
PROCEEDINGS OF THE ACADEMY OF 
exactly how the great changes of plumage to which the bird is subject, are 
produced. 
Adult. — Bill horn, deepening into black ; feet black. Pileum and occipital 
crest brownish-black ; this color extending much below the eyes, and occupy- 
ing the feathers on the ramus of the inferior maxilla. Acuminate feathers of 
the neck light yellow. Back, wings, tail, upper wing coverts, under tail 
coverts as far as the flanks, deep blackish-brown. Under parts, from chin to 
abdomen, and neck all round, (except the yellow acuminate feathers,) pure 
white. 
The above is the plumage of the fully adult bird, and is comparatively not 
often met with. A more usual state of plumage (described by Lawrence and 
figured by Audubon* as “fully adult, ”) is as follows : 
Nearly adult. — Generally as in the preceding, but with a row of brown spots 
across the breast ; the sides under the wings transversely barred with white 
and brown ; the purity of the dark color of the abdomen interrupted by some 
touches of white. The legs still wholly black, and the tail feathers projecting 
as much as in the fully adult. 
Now, as a somewhat younger stage than the preceding, we have the fol- 
lowing 
Intermediate stage , (No. 1275.) — The band of dark spots across the breast 
has widened and enlarged, so that the whole breast appears brown, mottled 
with white ; the sides under the wings are conspicuously barred with white 
and brown ; the white of the under parts is continued down over the abdomen 
to the under tail coverts ; the pure brown of these parts which obtains in the 
adult, now only appearing as transverse bars among the white. The upper 
tail coverts and some of the wing coverts are barred with white. The bases 
of the primaries are inferiorly white. The central tail feathers now only 
project an inch. The tarsi are quite changed in color; they are now irregularly 
blotched with chrome yellow, — the hind toe and nail being of this color. 
The above changes are very gradual, and readily identifiable ; the quo modo 
of their production may be thus summed up : In the adult the white and 
brown occupy distinct and well-marked regions ; and the two colors are 
separated by trenchant lines of division. The younger the bird, the more 
this distinctness of definition of colors is lost, — the white invading and barring 
the brown, and the brown invading and mottling the white, wherever the 
two join. Then also the feet lose their black, and are variegated with yellow. 
Besides the above, we find a state characterizable thus : 
Duslcy stage. — The bird is very nearly unicolor : blackish-brown all over; 
this color deepening into quite black on the pileum ; lightening into fuliginous 
brown on the abdomen, with a slight gilding of the black on the sides of the 
neck. The whitish bases of the primaries exist. The feet are in the chromo- 
variegated condition. The central tail feathers scarcely project half an inch. 
In the last edition of the Manuel d’Ornithologie, Temminck corrects various 
errors committed in previous editions, and gives, as his mature opinion, four 
“ varieties” of this species. By examining his diagnoses, it will be seen at a 
glance that his “ variety C” is the fully adult plumage above characterized ; 
of which he says truly that it is “ assez rare.” His “ B ” is our second stage ; 
his “ A ” is abou^our third stage ; while his “ D ” is the fusco-unicolor stage 
just given. In/his earlier editions lie maintains that this dusky stage is 
absolutely independent of sex ; but latterly he says that it is possible that the 
dusky birds are females ; the white-bellied ones males. Ornithologists main- 
tain very diverse views on this subject ; but I believe it is generally supposed 
that this state of plumage is not indicative of either sex, but simply of imma- 
turity. S. 
Now I tliinfe that the four plumages which Temminck describes as adults 
* I have Audubon’s original specimen before me. It agrees minutely with his plate; and is also 
the specimen from which Lawrence’s description in the General Report was taken. 
[May, 
