104 BULLETIN 50, UNITED STATES NATIONAL MUSEUM. 
ridged, straight or nearly so for basal half or more, then gradually 
more and more decurved to the distinctly uncinate tip of maxilla; 
tomia nearly straight, minutely but distinctly notched subter- 
minally (more slightly so on mandibular tomium); gonys distinctly 
convex and prominent basally, gently convex or nearly straight and 
ascending terminally, the tip of mandible forming a minute slightly 
recurved point. Nostril exposed, separated more or less widely 
from feathering of latero-frontal anti, longitudinally oval, with an 
internal tubercle showing distinctly within posterior portion, mar- 
gined above by a more or less broad extension of the membraneous 
integument of the nasal fossa. Rictal bristles absent; feathers of 
chin, etc., without distinct terminal sete, but their webs semi- 
decomposed, bristle-like. Wing moderate, much rounded, the longest 
primaries projecting very little (sometimes not at all) beyond second- 
aries; fourth, fifth and sixth, fifth, sixth and seventh, or fifth and 
sixth, primaries longest, the tenth (outermost) a little more than 
half (f. plumbea) to two-thirds (MJ. boucardi) as long as the longest, 
the eighth slightly shorter to decidedly longer than secondaries. 
Tail two-thirds to slightly more than three-fourths as long as wing, 
strongly rounded (graduation equal to less than distance from 
nostril to tip of maxilla), the rectrices (12) rather narrow to rather 
broad (MM. plumbea), rounded terminally. Tarsus much longer 
than whole culmen, two-fifths as long as wing or a little more, the 
acrotarsium distinctly scutellate, the planta fused (nonscutellate) ; 
middle toe, with claw, much shorter than tarsus; outer toe, without 
claw, not reaching to middle of subterminal phalanx of middle toe, 
the inner toe slightly shorter; hallux about as long as inner toe, 
but much stouter; basal phalanx of middle toe united to outer toe 
for much the greater part, to inner toe for not more than basal half 
(for less than basal half in Jf. boucardi); claws moderate in size and 
curvature, much compressed, that of the hallux decidedly shorter 
than its digit. Plumage full and blended, that of rump (and to a 
less extent that of flanks also) much lengthened, more lax; feathers 
of pileum short and blended in M. plumbea, more elongated and 
distinctly outlined in other species; rictal and postocular regions 
naked, the loral and frontal regions more or less scantily feathered. 
Coloration.—(1) Adult males uniform black, including outer sur- 
face of wings; adult females brown, the head more dusky. (ID 
Adult male plain slate color, the wing-coverts spotted with white; 
adult female similar but under parts bright tawny. (IIT) Adult males 
brown above, the head and neck slate color or olive, the wing-coverts 
with or without white spots; under parts gray or slate color, darker 
(sometimes black) on throat, the flanks brownish; adult females 
duller, brownish or rufescent below, or (in M. lemosticta) similar to 
the male but the black throat barred with white. (IV) Adult males 
