116 



BULLETIN 86, UNITED STATES NATIONAL IMUSEUM. 



Rio Negro, Brazil; west to the upper Rio Negro; the Rio Jurua; 

 Cachoeira and Bom Lugar on the Rio Purus ; Jamarysinho on the Rio 

 Madeira; the Rio Guapore, Brazil; the Moxos region, northeastern 

 Bolivia; and Matto Grosso, Brazil; south to Matto Grosso and Per- 

 nambuco, Brazil ; and east to Pernambuco and Para, Brazil. 



Remarks. — Individual and sexual variation have been already dis- 

 cussed in the account of the species above. This race, so far as re- 

 ported, occupies a much larger geographical area than the others, 

 and its known range will probably greatly increase as the result of 

 future explorations. All of the specimens examined will be found 

 listed in the table of measurements appended. 



Measurements of specimens of Chordeiles rupestris rupestris. 



+ 



1 Used in measurement averages on p. 115. 



CHORDEILES RUPESTRIS XYOSTICTUS, new subspecies. 



Chars, subsp. — Similar to Chordeiles rupestris rupestris, but some- 

 what larger; upper surface, including the wing-coverts, much paler, 

 more buffy (less grayish), the dark markings much smaller; and 

 breast more heavily spotted. 



Description.— Type, adult male. No. 16599, U.'S.N.M.; Bogota, 

 Colombia; W. Evans. Upper surface pale drab, shading to ochra- 

 ceous buff on the outer part of the scapulars, spotted, vermiculated, 

 obscurely streaked, and narrowly and brokenly barred with broc- 

 coli brown, the barring most evident on upper tail-coverts and 

 scapulars, the scapulars also a little barred and narrowly streaked 

 with dark brown, between clove brown and hair brown, and the 

 pileum conspicuously strealfed with the same; tail cream white, the 

 two central feathers basally rather light broccoli brown, distally 

 hair brown, irregularly barred and finely mottled with a dark gray- 

 ish brown, between clove and hair brown; the outer vane of outer- 

 most rectrix (excepting a very narrow light brownish edge and a 

 broad subterminal white space) and broad tips on all the rectrices 

 save the middle pair, of the same dark brown as the bars on the mid- 

 dle tail-feathers ; primaries of the same brown, but somewhat darker, 

 the four outermost unmarked, the next four with their bases (ex- 

 cepting the outer vanes) and all but the broad brown tips, cream 

 white ; rest of primaries and all of secondaries narrowly tipped with 



