606 AVIAN GENUS MYIARCHUS RIDGWAY. 



mcluded within the genus Myiarchns, as generally understood, the 

 chief structural characters of which may be tabulated as follows: 



a '. 15111 nciirly cylindrical, its depth at gonj'deal angle nearly c({ual to its width at 



the same place M yiakciiI' s. 



a K Bill depressed, its depth at gonydeal angle decidedly less than its width at the 

 same ])lace. 

 ft'. Nostrils distinctly lateral; widtli of bill at frontal feathers much less than 

 length of gonys. 

 c' Tarsus much shorter than length of bill from rictus; lateral outlines of bill 



contracted at tiji Onychopterus. 



0'^ Tarsus as long as bill from rictus; lateral outlines of bill not contracted at 



tip E lUB ATES. 



6-. Nostrils superior; Avidth of bill at fnmtal feathers e([ual to length of gouys. 

 (Tarsus much shorter than length of bill to rictus.) Deltarhynchus. 



The synonymy of these generic or subgeneric groups is as follows : 



1. Myiarchus Cabauis. 



MyiarchuH Cab., in Tschudi, Faun. Per., Aves, 1845, 152. Type, Muscicapti ferox Gm. 

 Kaupornis Boxap., Ann. Sc. Nat., ser. iv, Zool., i, 1854, 133. Type, Mijiohiuti atolidus 



GOSSE. 

 Myionax Cab. and Heine, Mus. Hein., ii, 1859, 73. Type, Muscicapa crinita Linx. 

 "Despotiu a Kavp, 1851," Gray", Hand-1. i, 1871, 363. Type, Muscicapa ferox Gm. 



This section includes, besides the type {M. ferox), M. crinitus (Linn.), 

 M. mexicamis (Kaup), M. cinerascens Lawr., M. yucatanensis Lawr., 3f. 

 tyrannulus (Miill.), M. phxrocephahiH Scl., and all the West Indian 

 species except M. barhirostris (Sw.), together with, as a matter of course, 

 their various geographical races or subspecies. 



2. Onychopterus Keichenbach. 



Onychopterus Reich., Av. Syst. Nat., 1850, t. Ixv. Type, Tyrainms tiihvrru lifer l)'i >rb. 

 and Lafr. (= Myiarchus atriceps Cab.?). 



This includes, besides the type, M. lawrencii (Gir.) and M. barhirostris 

 (Sw.), together with the various geographical races of and species 

 allied to the former species. 



3. Eribates Kidgway. 



Eribatea Ridgw., MS. Type, Myiohius maifnirostris Gray. 



4. Deltarhynchus Kidgway. 



DeUarhyntliux Kidgw., M.S. Type, Myiarchns tlummulatus JjAWK. 



Species which I have not examined, and therefore can not assign to 

 their proper sections, are the following: M. ccphalotes Tacz., M. pelzeJni 

 Berl., M. pluvonotHs Salv. & Godni., M. apicnlia Scl. & Salv., J/, tricolor 

 Pelz., M. semirufus Scl., and JF. iiiquietus Salv. «& Godm. 



Myiarchus yucatanensis Lawr. 



Although described by Mr. Lawrence in 1871 (Proc. Acad. Xat. Sci., 

 Philad.. 1S71. }>. -•>">), My inn-Juts yiicatfoirnsis remained little known 

 until ISST, wIm'U the present wiitcr gave it detinite cliaractcrs in liis 



