SULIDZ. 435 
THE INDIAN TROPIC BrrRD.' 
Length, including elongated central tail-feathers which project 
from 8 to 59 inches beyond the rest of the tail, 20 to 23; 
expanse, 37 to 40; tail, 7'5 to 10°5 ; wing, 10°75 to 11°75 ; tarsus, 
1 ; bill at front, 2°4. 
Trides deep brown ; legs and hind-toe with web white, tinged 
bluish and creamy-yellow ; rest of feet and claws black. 
A broad conspicuous black crescent in front of the eye, and a 
narrow black line, from the gape to nostrils, and nostrils to cul- 
men, dividing the feathers fromthe bill ; the whole forehead, 
front part of the crown, ear-coverts, and entire lower parts, includ- 
ing wing lining and axillaries, pure white ; a black line from the 
posterior angle of the eye, running round the back of the nape, 
where it forms a more or less conspicuous half-collar ; hind-crown 
and nape inside the half-collar white, each feather with a 
triangular black bar near the tip; carpal joint of wing, four or 
five posterior primaries, all the secondaries, the primary coverts 
except those of the first five quills, the greater and median 
coverts pure white ; winglet, greater-coverts, shafts and 
outer webs of the first five primaries, together with a 
narrow stripe along the shaft of the inner web, black ; 
the extreme tips and inner webs of these feathers white ; 
tertiaries and their greater-coverts black, narrowly margined on 
the exterior webs and tipped with white; the lesser secondary- 
coverts similar; the entire back, rump, scapulars and upper 
tail-coverts white, closely barred with black, the bars being 
slightly cuspidate on the upper back, and the longest scapulars 
almost devoid of barring ; tail-feathers white, their bases black 
shafted, and the lateral feathers mostly with an arrow-head bar 
or spot near the tips. 
The above description is reproduced from “Stray Feathers.” It 
still remains doubtful whether this is an immature phase of 
P. ethereus or a new species. 
Several specimens have been obtained at different-times on the 
Mekran Coast. 
Trise, Piscatores. 
Feet entirely webbed, the hind-toe articulated on the inner 
side of the tarsus, directed inwards, and in some slightly forwards 
joined to the inner front-toe by web, forming a most powerful 
oar; legs short; wings long or moderate ; bill varied. 
Famity, Sulide. 
Bill stout, straight ; wings long ; tail moderate, wedged; feet 
fully webbed ; size large; of oceanic habits. 
Genus, Sula, Brisson. 
Bill lengthened, compressed, straight, thick at base, acute 
and compressed at tip; margin serrated; culmen convex ; upper 
