(55 ) 



distinctly striated. I have examined four of the specimens npon which von Pelzeln 

 based his X. approximans ; two of them (<? ad., Rio Icanna; 3 ad., Rio Negro) 

 differ in no way from ordinary genibarbis, whereas the two others ( ? , Rio Negro ; 

 3, Borba) are rather duller and more rufescent on the lower parts. Both are 

 3'onng and agree in the tone of the under-snrface with an immature bird from the 

 Caura River. I am unable to see any constant differences between specimens from 

 Cayenne, Orinoco, and Amazonia. The length of the wing varies from 03 to 67 mm. 

 in the males, from 00 to 04 mm. in the females ; the bill measures 14 to 15i mm.* 



b. X. genibarbis littoralis Scl. 

 Xmops litlorulis Sclater, P.Z.S. 1861. p. 379 (Esmeraldas, Western Ecuador). 



Ilab. Western Ecuador. 



This form differs from X. g. genibarbis chiefly by having the lower parts 

 tinged with greenish olive; the throat is more yellowish, the pileum always 

 uniform brown, the back of a purer, less rufescent brown, and the whitish spots 

 on the foreneck much less numerous. Wing 60 — 04; tail 40 — 49 ; bill 14 — 15 mm. 



Material : 12 specimens (of both sexes) from Western Ecuador. 



c. X. genibarbis mexicanus Scl. 

 Xenops mexicanus Sclater, P.Z.S. 1856. p. 289 (Cordova, Eastern Mexico). 



Hub. Central America from Eastern Mexico (Vera Cruz) down to Panama. 



Differs from X. g. littoralis, with which it shares the coloration of the 

 foreneck and crown by its much brighter, warm rufescent-brown underparts 

 and back. Bill large and stout, as in X. g. genibarbis and X. g. littoralis. Wing 

 01—07 ; tail 48—52 ; bill 14—15 mm. 



Material : 20 specimens from Eastern Mexico, Guatemala, Costa Rica, Chiriqui, 

 Vcragua, and Panama. 



d. X. genibarbis pelzelni n, snbsp. 



X. genibarbis (nee Illiger) Pelzeln, Zur Orn. Brasil. i. (18G7) p. 41 (Rio de Janeiro, S. Paulo). 



Ilab. South-eastern Brazil : from Bahia to S. Paulo. 



Type in Vienna Museum : No. 19,321. 3 ad., Ypanema, S. Paulo, August 

 1821. Collected by J. von Natterer. 



Differs from the three foregoing races by its smaller bill, which is not 

 ouly considerably shorter, but also very much narrower and weaker. The wings 

 are much shorter. The throat is uniform buffy white without any dusky edges 

 to the feathers, the light spotting on the foreneck is altogether absent or 

 scarcely indicated by a few pale brownish shaft-lines ; the ground-colour of the 

 underparts decidedly brighter, about " wood-brown " (Ridgw. Xomencl. iii. fig. 19) ; 

 the light cross-band on the uuder-surface of the wing buff (instead of ochraceous 

 buff) ; the top of the head always uniform rufescent-brown without pale shaft- 

 stripes. Wing 55—58 ; tail 47—49 ; bill 12— 12* mm. 



Examined: 1 3, 1 ? ad., Registre do Sai (prov. Rio) ; 1 3 jr., Rio de Janeiro: 



1 3 ad., Ypanema— Mus. Vindob. ; 3 ad., Rio de Janeiro (Mus. Brit, and Triug) ; 



2 ad., Bahia (Brit. Mus.). 



• Examined : 1 3 ad., Trata, Pari ; 1 ? jr., Itaituba, Santarem ; 1 3 ad , Teffe ; 1 3 ad., 1 ° jr., 

 Kio Negro ; 1 3 ad, It. Icanna ; 1 3 jr. Borba : types of X. ajppTOSevmaru Telz. ; 2 J (J, 1 ? , Cayenne ; 

 2 3 3, 1 ? . Cawacusa, Brit. Guiana ; 4 3 3, 4 ? ? , Caura, Venezuela 2 3 3, 2 ? ? , Upper Orinoco ; 

 I Bogota skins ; 1 ad., East Ecuador ; 2 °. ? , Guayabamba, North Peru. 



