I 



BIEDS OF NORTH AND MIDDLE AMERICA. 751 



Genus ENDOMYCHURA Oberholser. 



Micriiriaa ^not of Reitter, 1875) Grant (O.), Cat. Birds Brit. Mus., xxvi, 1898, 

 594. (Type, by original designation, Brachyrhamphus hijpoleucus Xantus or 

 Uria craven Salvadori.) 



Endomychura b Oberholser, Proc. Ac. Nat. Sci. Phila., June 2, 1899, 201. 

 (New name to replace Micruria Grant, preoccupied.) 



Small Phalerinse (wing 113-128 mm.) with small and slender bill, 

 resembling BracJiyram'pJius, 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 antioe, 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 primaiiea pure wliite (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). 



" Mi/cp6s, small; -\- Uria. (Richmond.) 



& 'Evdonvxos, concealed; ovpa, tail. (Richmond). 



