BIRDS OF NORTH AND MIDDLE AMERICA. 751 
Genus ENDOMYCHURA Oberholser. 
Micruria ¢ (not of Reitter, 1875) Grant (O.), Cat. Birds Brit. Mus., xxvi, 1898, 
594. (Type, by original designation, Brachyrhamphus hypoleucus Xantus or 
Uria craveri Salvadori.) 
Endomychura > OBERHOLSER, Proc. Ac. Nat. Sci. Phila., June 2, 1899, 201. 
(New name to replace Micruria Grant, preoccupied.) 
Small Phalerine (wing 113-128 mm.) with small and slender bill, 
resembling Brachyramphus, but with tarsus decidedly longer than 
middle toe without claw, instead of much shorter, rectrices only 12, 
instead of 14, and without distinctive breeding plumage. 
Bill small, slender, and compressed, the exposed culmen much 
shorter than tarsus, its depth through gonydeal angle much greater 
than its width at latero-frontal anti, much less than half the distance 
from nostril to tip of maxilla; culmen faintly depressed sub-basally 
slightly elevated basally, gently curved from near base to tip; gonys 
straight, ascending terminally, its rather prominent basal angle far 
anterior to nostril; nostril pyriform (the narrow end distal), pos- 
teriorly in contact with latero-frontal feathering, the latter slightly 
but distinctly indented at base of culmen; mandibular rami for 
greater part feathered, the ill-defined malar antia about on same 
vertical line as latero-frontal antia; mental antia about on line with 
anterior end of nostril. Wing small, the longest primary (first or first 
and second, from outside) exceeding distal secondaries by a little 
more than half the length of wing. Tail about three-sevenths as 
long as wing, decidedly rounded, nearly concealed by coverts; rec- 
trices 12. Tarsus longer than middle toe without claw (but shorter 
than middle toe with claw), the acrotarsium reticulate; outer toe 
as long as middle toe, the inner toe as long as first two phalanges of 
middle toe. 
Coloration.—-Upper parts plain dusky slate color or slate-gray, the 
scapulars and interscapulars darker centrally; under parts immacu- 
late white; no special breeding plumage. 
Range.—Islands along coasts of Lower California and southern 
California. (Two species.) 
KEY TO THE SPECIES OF ENDOMYCHURA. 
a, Under wing-coverts wholly immaculate white; upper parts blackish slate; inner 
webs of distal primaries pure white (or nearly so) for greater part; slate-colored 
feathers of sides and flanks conspicuously tipped with white or grayish white. 
(Monterey Bay, California, to Cape San Lucas, Lower California.) 
Endomychura hypoleuca (p. 752). 
aa. Under wing-coverts mostly brownish gray; upper parts sooty slate or nearly seal 
brown; inner webs of distal (and other) primaries grayish brown, but little 
paler than outer webs, except at base; feathers of sides and flanks without 
whitish tips. (Coasts and islands of southern Lower California, from Cape San 
Lucas to Espiritu Santo and Natividad islands.) ..Endomychura craveri (p. 753). 
° Mixpés, small; + Uria. (Richmond.) , 
b ’Evdéuvxos, concealed; odpé, tail. (Richmond). 
