70 U. S. P. R. K. EXP AND SURVEYS ZOOLOGY GENERAL REPORT. 
thickened and stiffened so as even to be spinous, this character perceptible in the feathers on 
the back, though diminishing towards the head. 
According to Gould, fully adult specimens of this species have the three outer tail feathers 
entirely black, with white tips, the narrow bars being characteristic of immaturity, as are also a 
greater distinctness of the freckles on the wing and the white edgings to the primaries not 
found in the adult. 
In the female the green tints are said to be replaced by brownish, as also the upper part of 
the carmine ; the hinder portion of the under parts is as in the male. The white pectoral 
crescent is also indicated by grayish. 
The Trogon elcgans is somewhat similar to this species, but has a longer tail. 
In the monograph of* Trogonidae, Gould figures his Trogon ambiguus from northern Mexico, 
distinguished by the finer mottling on the wing and the replacing of the narrow bars on the 
tail feathers by black dottings. This is precisely the character of No. 4338, which would, 
therefore, if distinct, bear this name. As, however, the other characters are so similar, it 
would seem as if the ambiguus were merely another stage of plumage of T. mexicanus. A speci- 
men labelled Trcgcn amliguus, in the collection of the Philadelphia Academy, differs, however, 
in having a much greener gloss to the feathers of the body. The black of the forehead extends 
further on the crown. The middle tail feathers are more green than coppery ; the carmine of 
the belly is less intense. The mottling of the wings and tail is much the same. 
List of specimens. 
Catal. 
No. 
Sex. 
Locality. 
When col- 
lected. 
Whence ob- 
tained. 
o g- 
No. 
L'gth. 
Ex- 
Wing. 
Tail. 
Tar- 
Mid'le 
toe. 
Its claw 
alone. 
Bill 
Along 
gape. 
Specimen 
measured 
Remarks. 
4338 
do 
4339 
do 
d' 
Boquillo, New 
Leon, Mex. 
April, 1853 
Lt. Couch . . . 
138 
10.75 
11 50 
11.25 
12.00 
16.25 
5.25 
5.10 
5.00 
5.00 
Fresh .... 
Iris br'wn, 
billyel'w. 
Dry skin. 
6 75 
.61 
.90 
.26 
.65 
.85 
3 
April, 1853 
Lt. Couch . .. 
145 
14.2; 
An ... 
6.75 
.60 
.70 
Dry skin. 
1 
1 
