SULID^ — THE GANNETS — SULA. 



183 



bO.OO ; wing, 15.80; tail, 9.00; culnien, 3.50; depth of bill through base, 1.10; tarsus, 1.50; 

 middle toe, 2.40.^ Younger : Upper tail-coverts and tail as in the preceding ; rest of the plumage 

 sooty gray, the head and neck paler, sometimes nearly white. " Bill lead-color, with a hand of 

 yellow across the forehead and two yellow patches at the base of the lower mandible ; feet and 

 legs red " (W. T. March, manuscript). Young, first plumage (77005, Dominica, West Indie.s, 

 April, 1879 ; Dr. H. A. Nicholls) : Above, sooty grayish brown, the remiges and rectrices hoary 

 slate ; head, neck, and lower jjarts light smoky gray. Bill blackish. Older ? : Similar, but lower 

 parts, posterior to the breast, dirty white, the head and neck sooty grayish brown ; bill blackish. 



The plumage of this species is so exceedingly variable as to render it quite doubtful whether the 

 various phases noted (scarcely two examples in a series of fourteen specimens being alike) are 

 wholly dependent on age or sex. Some examples in the immature dress have the head, neck, and 

 jugulum (!) nearly white, the remaining lower parts light sooty gray ; while others (apparently 

 younger) have the head, neck, and jugulum dark sooty brown, and the lower parts whitish — just 

 the reverse. At all stages it may be distinguished from S. eucogastra by the red feet and, usually, 

 the smaller size, especially of the bill and feet. 



In all adult examples, and in most young ones, the red color of the feet is sufficient to distin- 

 guish this species from S. leucogastra, independent of the shorter bill and difference of plumage. 

 There are two young specimens ^ in the collection, however, which, although apparently having 

 reddish feet (it being, of course, impossible to tell what the color was originally), agree best with 

 S. leucogastra in the size and shape of the bill, and in colors. In every respect they agree quite 

 closely with a specimen of unquestionable S. leucogastra from Jamaica, in which the feet seem to 

 be reddish, but which m life (so we learn from the label) had them " horny yellow." 



The claims of this species to a place in the North American fauna rest upon a specimen, exam- 

 ined by Professor Baird, in the collection of the Philadelphia Academy, labelled as from Florida, 

 and presented by Mr. Audubon, by whom it was considered as the Sulafasca (= leiicogadra'). It 

 is smaller than S. leucogastra, but of much the same shape and general appearance. The head, 

 neck, and whole under parts are white, the feathers of the sides tinged with brown. The back, 

 wings, and tail are dusky brown, the feathers of the back and the wing-coverts edged with whitish, 

 those of the rump and upper tail-coverts less distinctly. The middle tail-feathers are hoary gray 

 at the base, with whitish shafts ; the rest become darker, the shafts browner toward the exterior 

 of the tail. The colors of the naked parts are not distinguishable ; the legs and feet appear to have 

 been greenish dusky .^ 



Length, about 27.00 inches ; wing, 14.00 ; tail, 8.00 ; tarsus, 2.00 ; middle toe and claw, 3.00 ; 

 bill, about 3.25. 



1 The average measurements, given in the same sequence as above, of a series of fourteen specimens, 

 are as follows : 15.04 inches, 8.93, 3.26, 1.07, 1.34, 2.25. Upon comparing these figures with those on 

 p. 178, it will be seen that while the wing and tail are about the same average length as in aS^. leucogastra, 

 the bill is decidedly shorter and more slender, and the tarsus and middle toe also much shorter. 



2 Nos. 1963 (no locahty), J. J. Audubon ; labelled " Sulafusca, L.," and 21279, "off Meia-co-shima 

 Islands." 



^ If the specimen is really S. piscntor, the feet must have been I'ed in life ; otherwise it must be 

 S. leucogastra. 



