86 U. S&S. P. R. R. EXP. AND SURVEYS—ZOOLOGY—GENERAL REPORT. 
The bill of the young bird differs considerably from that of the adult. Instead of being 
nearly straight in its upper and lower outlines, with the tip compressed, truncate, and wedge- 
shaped, it is shorter, sometimes considerably broader, and with the outlines, the upper especi- 
ally, much curved to a terminal sharp point, instead of wedge. In the immature male (and 
female also, probably) the entire crown from the base of the bill to the occiput, has the feathers 
sometimes spotted with white, and tipped with orange red or yellow. Sometimes only the 
posterior half of the crown is so marked, thus indicating a nearer approach to maturity. The 
peculiar spotting is like that of Picus scalaris or nuttalli. The white is sometimes almost 
wanting. The shade of red varies with specimens from carmine to orange yellow, sometimes 
more decidedly yellow. This is the case in the original of Picus audubonii of Trudeau, now 
before me, (2803,) which, besides this character, has every other feature of a young bird, as 
shown by the curved broad bill, the loose, woolly texture of the feathers, &c. It is a little 
smaller than corresponding specimens from Pennsylvania, a difference perfectly intelligible, in 
view of its more southern locality, (Louisiana.) No. 1562, from Carlisle, however, is scarcely 
larger. 
Specimens vary a little in having the white streak above the eye continuous with the whitish 
on each side of the base of the bill. The white of the head and under parts is sometimes more 
extensive, and brighter. 
As a general rule the specimens of this species from the far west and north are appreciably 
larger than those from the more eastern States, in which again southern specimens are con- 
siderably smaller. I can detect no other difference, except size, in the Picus canadensis, as 
established by Mr. Audubon. With his typical specimens before me, I find them not even as 
large as the majority of the western skins; and while Mr. Audubon describes his male Picus cana- 
densis as measuring 10.50 inches, the wing 5.08, the tail 3.50, the specimen given in the P. 
Bor. Amer., from a still more northern locality, measured 11 inches, the wings 5.38, tail 4.25, 
and in no other way different either from them or Pennsylvania ones. It is to the larger variety 
from Canada that both Picus phil/ipsii and Picus martinae belong. With the original specimens 
of Mr. Aububon before me, I find every characteristic of the young bird in the soft bones, the 
woolly, soft feathers of the under parts, &c. In the ‘‘P. phillipsii’’ the characters. are precisely 
as in the young males described from Carlisle. The top of the head is irregularly spotted with 
orange red in one specimen, and orange yellow in the supposed female. In ‘‘Picus martinae,”’ 
again, there is rather more of a dull orange yellow patch on the crown, the feathers, even the 
black ones, spotted with white, as in 1562 from Carlisle. The immaturity of the red or yellow 
markings in all these specimens is clearly shown by their lacking the symmetry seen in known 
adults, the outlines being all irregular and the colors more or less interrupted and unsymmetrical 
in places. In one specimen from Carlisle, nearly adult, (2423,) the top of the head or crown is 
spotted with yellow, the occiput with red. 
It may be assumed as a general principle, in reference to the black spotted woodpeckers of 
North America belonging to the restricted genus Picus, that whenever the crown is spotted 
with red or yellow either partly or entirely, the specimen is immature, and may probably be of 
either sex, while the red is found only in the adult male, and confined to an occipital line. 
The only exceptions are in Picus scalaris, where the entire upper part of the head is red spotted, 
and P. nuttallit, where the posterior half is thus marked. In the young of this last species, 
however, the anterior half of the head above is similarly spotted with red. 
