BIRDS OF NORTH AND MIDDLE AMERICA. 663 



Myiodynasteshemichrysiis Lawrence, Ann. Lye. N. Y., ix, 1868, 1 14 (Costa Rica). — 

 Frantzius, Journ. fiir Orn., 1869, 308 (Costa Rica). — Scl.\ter, Cat. Birds 

 Brit. Mu.'f., xiv, 1888, 188 (Calovevora and Calobre, Panama.) — Salvin and 

 GoDMAN, Biol. Centr.-Am., Avcs, ii, 1889, 50, pi. 38, fig. 1 (Barranca, Costa 

 Rica; Chitra, Calovevora, and Calobre, Panama). 



[Myiodynantes] hemichrysus Sclater and Salvin, Nom. Av. Neotr., 1873, 50. — 

 Sharpe, Hand-list, iii, 1901, 129. 



Myiodynastes superciliaris Lawrence, Ann. Lye. Nat. Hist. N. Y., viii. May, 1867, 

 470 (Barranca, Costa Rica; colL U. S. Nat. Mus.). — Salvin, Proc. Zool. Soc. 

 Lend., 1870, 198 (Chitra, Calovevora, and Calobre, Panama). 



[Pitangus] superciliosus [error for superciliaris] Gray, Hand-list, i, 1869, 357, no. 

 5437. 



GenLis MEGARTNCHUS Thunberg. 



Platyrhynchus (not Platyrinchiis Desmarest, 1805) Temminck, Tabl. Meth., 1822, 



23. (Type, Lanius pitangva Linnseus.) 

 Megarynchus Thunberg, Dissert, de genre Megaryncho, 1824, 2. (See Heine, 



Journ. fiir Orn., 1859, 337.) (Type, by elimination, Lanius pitangva Lin- 



najus or Megarynchus hrunneus Thunberg. ) « 

 Scaphorkynckus Maximilian, Beitr. Xaturg. Bras., iii, 1831, 982. (Type, S. sul- 



phuratus Maximilian, = Lanwts pitangva Linnaeus.) 

 Megastoma Swainson, Classif. Birds, ii, 1837, 225. (Type, M. flariceps, etc.,= 



Lanius pitangva Linnseus.) 



Large Tyrannidee (wing about 110-125 mm.), with exposed cul- 

 men much longer than tarsus and curved throughout, gon^^s twice as 

 long as mandibular rami, tail less than three-fourths as long as wing, 

 crown dusky olive with a concealed patch of yellow or rufous and 

 surrounded by a white ring, broad dusky band on side of head, upper 

 parts plain olive and under parts bright yellow, becoming white on 

 throat. 



Bill large, broad, and slightly decurved, about as long as head, its 

 width at anterior end of nostrils equal to more than half the distance 

 from nostril to tip of maxilla and much greater than its depth at 

 same point, the lateral outlines more or less convex anterior to mid- 

 dle portion; exposed culmen much longer than middle toe with claw, 

 very distinctly ridged, more or less strongly convex throughout, more 

 strongly decurved terminally, the tip of maxilla distinctly uncinate; 

 gonys more than twice as long as mandibular rami, straight or xevj 

 faintlj'- convex, ascending terminally, rather prominent basally, 

 faintly ridged, at least terminally; maxillar}^ tomium more or less 

 obvioush" concave, distinctly notched subterminally. Nostril only 

 partly exposed, longitudinally oval, overhung by rather broad mem- 

 brane. Rictal bristles distinct, but relativeh^ rather small; feathers 

 of chin with distinct recurved bristly points, those of antrorse latero- 

 frontal feathers with distinct decurved (arched) bristly points, those 

 of malar antife with straight antrorse or semierect setse. Wing rather 

 long and pointed, the longest primaries exceeding distal secondaries 



o The latter I am not able to identify. 



