556 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
Al[nous] leucocapillus Riweway, Man. N. Am. Birds, 2d ed., 1896, 48 (not of 1st 
ed., 1887). 
Micranous leucocapillus SauNDERS, Cat. Birds Brit. Mus., xxv, 1896, 145, part 
(Glovers Reef, Brit. Honduras; Fernando Noronha Island, off n. Brazil 
St. Paul Rocks; Ascension Island).—Satvin and Gopman, Biol. Centr. - 
Am., Aves, iii, 1903, 415 part (Glovers Reef and Southwest-of-all Cay, Brit. 
Honduras).—Nico11, Ibis, 1904, 36 (St. Paul Rocks, middle Atlantic Ocean 
habits). : 
[ Micranous] leucocapillus SHarPr, Hand-list, i, 1899, 138, part (Caribbean Sea; 
“KE, America’’). 
Megalopterus minutus atlanticus Maruews, Birds of Australia, ii, pt. 4, Nov. 1, 
1912, 423 (Ascension Island; St. Paul Rocks; Fernando Noronha; Carib- 
bean Sea; British Honduras). 
MEGALOPTERUS MINUTUS DIAMESUS (Heller and Snodgrass). 
CLIPPERTON NODDY. 
Similar to M. m. melanogenys * “but differs in being darker on the 
shoulders,.on the lower part and sides of the neck and on the sides 
of the head, and in having a more slender and shorter bill and shorter 
tarsus.” | 
Adults (sexes alike).—‘ Forehead and top of head almost pure 
white, back part of head and nape with a plumbeous tinge. Back 
of neck plumbeous, darkening into dark plumbeous on shoulders 
and then into brown on the mantle. Rest of upper parts, except 
upper tail-coverts and tail, dark dusky brown; outer webs of outer 
primaries sooty brown, almost black; upper tail-coverts and tail 
dark plumbeous-gray. Under parts dark dusky brown darkest on 
lower breast and on belly. Lower tail-coverts somewhat lighter 
plumbeous-brown. Tail below same color as above. Lores and 
line extending from lores over eye to middle of posterior side of 
eye, black, a small white spot in this line above posterior part of eye. 
Lower two-thirds of lower eyelid white. Cheeks deep dark plumbeous, 
pale color of back of head and neck scarcely extending upor lateral 
parts.” 
Immature.—‘ Top of head pure white, with a few brown feathers 
posteriorly. Outer webs of outer primaries blackish brown, that of 
the first almost black. Lores, supraocular line and cheeks dusky 
brown. All other parts pure dark brown, but with no dusky tinge 
except on the lower part of the throat.” 
a See p. 554. 
“In Micranous hawatiensis [i. e. M. minutus melanogenys] the pale slaty plum- 
beous color of the back of the head and neck reaches so far ventrally on the sides 
of the head and neck and even on the upper part of the breast, that there is distinctly 
marked off on the chin and throat a median longitudinal area of dark plumbeous 
brown well defined on each side against the paler lateral parts.’’ (Heller and 
Snodgrass.) . 
