BLUE YELLOW-BACKED WARBLER. 
65 
GENUS IV. PARULA. THE LITTLE WARBLERS. 
Gen. Oh. Bill, considerably shorter than the head, slender and acuminate. Tarsus, longer than the hind toe and 
claw. Height of keel, not exceeding one-half the width of sternum. Coracoid bones, equal in length to the top of keel. 
Birds of this genus, although small in size, are rather stout in form. 
PARULA AMERICANA. 
Blue Yellow-backed Warbler. 
Parula Americana Bon., List of Birds of North America, 1838. 
DESCRIPTION. 
Sp. Ch. Size, small. Wings, rather long. Tail, square and slightly emarginate. Sternum, not stoutly built. 
Tongue, quite thick and fleshy at the basal half, then suddenly becomes thiu and acuminate. The end is cleft for 
five-hundredths of an inch and the divided portions are coarsely ciliated. This tongue is quite unique among 
Warblers, differing from any others that I have seen in having a fleshy base, terminating abruptly in a thin point. 
Color. Adult male. Above, slaty-blue, brightest on the head; with a large patch of greenish-yellow in the 
middle of the back. Wings and tail, brown, edged with bluish; the six outer feathers of the latter are spotted 
subterminally, on the inner webs, with white. The two rows of upper wing coverts are tipped with white, forming 
rather broad bars. The blue above extends down on the sides of the head and neck, but is rather dusky on these 
parts. The lores are black, and there is a spot of white on the upper and lower eyelids. The sides and flanks are 
tinged with pale bluish. Throat and breast, yellow, with a patch of chestnut-brown across the upper part of the 
latter, which is sometimes preceded by a narrow line of the same color as the sides of the neck. The remaining 
under surface, including under tail coverts, under wing coverts and closed wing beneath, white. Ventral region, 
tinged with yellow. 
Adult female, similar to the male, but the chestnut of the breast and the yellow of the back is not as bright or 
as extended. 
Young male, similar to the adult female. 
The young female has the yellow beneath less extended and without a trace of chestnut. There is also but a 
slight indication of the yellow patch above. In all stages the irides are brown; upper mandible, brown; lower, 
whitish; feet, brown. 
OBSERVATIONS. 
This pretty little species may be distinguished at once from all others by the ever present yellowish-green patch 
upon the back, combined with the yellow throat. Distributed during the breeding season throughout Eastern 
United States from Virginia north to Canada; winters in Mexico, Central America, West Indies and Key West. 
DIMENSIONS. 
Average measurements of twenty-three specimens. — Length, 4-75; stretch, 7-30; wing, 2'30; tail, 1-70; bill, 
•40; tarsus, -63. Longest specimen, 4-90; greatest extent of wings, 7-70; longest wing, 2-85; tail, 1-85; bill, -49; 
tarsus, ’75. Shortest specimen, 4-25; shortest extent of wings, 7‘70; shortest wing, 2-20; tail, 1*40; bill, -35; 
tarsus -59. 
DESCRIPTION OF NESTS AND EGGS. 
Nests. The accompanying description is from Mr. Brewster. “A nest discovered by Mr. Deane and myself, at 
Stoneham, Mass., in June, 1868, was hung in a drooping spray of hemlock, about eight feet from the ground, near the 
extremity of the limb, and differs in structure from any other that I have seen. In appearance it strongly resembles 
the domicile of Lcterus Baltimore, being entirely open at the top, not in the least purse-shaped as in the case of other 
nests of this species which I have examined, and which also differ in having the entrance hole at the side. It is 
composed entirely of long moss curiously interwoven. The whole structure is so delicate and frail that the eggs, 
which were three in number, could be plainly seen through the bottom as I stood on the ground. Dimensions: 
external diameter, 2-25 inches, internal, 1-75 ; external depth, 2-62 inches, internal 2-50.” 
Some beautiful specimens of these nests, in the cabinet of my friend, Mr. H. A. Purdie, are also composed of the 
long, gray moss, but differ from that described above in being perfect little purses, with the entrance hole on the 
side. There is no other material used for lining than that of which the structures are made. . 
Eggs, usually four in number, white in color, spotted and dotted everywhere with light reddish-brown and lilac, 
but more sparsely on the smaller end. The largest spots are of brown and the smallest of lilac. Dimensions from 
•66 x -48 to -70 x -50. 
BIRDS OF FLORIDA. 
