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BULLETIN: MUSEUM OF COMPARATIVE ZOOLOGY. 
Sterna dougalli gracilis (Goutp). 
Two specimens, an adult ¢ and an adult 9, taken June 7 on a small island 
near Ishigaki. [Eggs were collected from June 19 to July 5.] These speci- 
mens are extreme of the slender-billed small form to which Gould’s name 
gracilis applies. Specimens from western Europe and Africa agree closely in 
measurements with those from eastern North America and the West Indies. 
The red bill claimed as a character of gracilis may be due to age, many young 
specimens from America having red bills, while in the adult birds it is black. 
The differences between the two races of the Roseate Tern in size and in measure- 
ments of the bill are well marked. 
The Liu Kiu Islands specimens agree in measurements with the. Australian 
form, upon which Gould based his S. gracilis, and there can be no doubt of 
their identity. 
The measurements of the two specimens are as follows : — 
No. Sex. Wing. Tail. Tarsus. Exposed Culmen. 
37,304 os 221 110 20.2 36.6 
387,305 g 216 109 19.4 36. 
Sterna fuliginosa crissalis (Barrp). 
Two specimens from a small island near Iriomote, adult g and adult Q, 
taken June 10. [Eggs, one in a clutch, laid on the rock, were taken June 1. ] 
Sterna bergii boreotis,? subsp. nov. 
Typr. — Mus. Comp. Zodl., No. 37,801. 
_ Asingle adult g in full breeding plumage from Ishigaki, June 15, 1899. 
[Said to breed on Ishigaki.] 
Subspecifie Characters. — As small as the pale gray Sterna bergii poliocerca of 
Tasmania and South Australia ; differing from it in having the wings, tail, and 
mantle very dark smoke gray, almost mouse gray. 
Color. — Type, adult ¢ in full plumage. Forehead, cheeks, lores, ear-coverts, 
neck all round, and whole under parts, including lining of wing and bend of 
wing, pure white ; crown and long occipital crest glossy black ; mantle, wings, 
rump, upper tail coverts, and upper surface of middle rectrices dark smoke 
gray, darkest on wings and middle of back, where the color is almost mouse 
gray ; primary quills white; Ist primary with outer web, a band along quill 
on inner web and tip blackish, with a silvery suffusion which is most marked 
toward centre of feather; broad outer margin of inner web, below the black tip 
1 The tails are measured to the end of the second rectrix, the streamer varying 
too much in length individually to be taken into account. 
2 Boreotis, northern. 
