THE GENUS CHORDEILES SWAINSON OBERHOLSEE. 11 



pi. 2, fig. 2), it seems necessary to separate all these American 

 species under the name — 



SETOCHALCIS/ new genus. 



Somewhat resembling Antrostomus Bonaparte (as restricted 

 above) , but interorbital region of frontals much wider ; palatines with 

 inflated posterior portion smaller, the postero-external angles more 

 sharply pointed and little if any extended backward beyond the 

 median part of the palatines ; vomer somewhat more sharply pointed ; 

 maxillo-palatines smaller, shorter, less sharply pointed and much 

 more widely separated ; the oval palatal opening between the halves 

 of the premaxillary more elongate; pterygoids not so far separated 

 from the basisphenoid, resting almost against it for the anterior half 

 of their length; rictal bristles without lateral filaments; second 

 primary (counting from the outermost) longest, the third but little 

 shorter, the first considerably shorter than the third and about equal 

 to the fourth (in Antrostomus the second primary is the longest, 

 but the third is decidedly shorter, the first still a little shorter, but 

 very much longer than the fourth) ; three primaries sinuate on their 

 outer webs, instead of two as in Antrostom/us; wing relatively shorter; 

 and pterylosis different.^ 



Superficially similar to Caprimulgus Linnaeus, but palatines very 

 differently shaped, the distance from their posterior border to the pos- 

 terior ends of the foramina in their middle portion much greater, and 

 these openings much smaller ; the postero-external angles of palatines 

 much more sharply pointed, and the postero-external outline laterally 

 much less convex, indeed nearly straight ; vomer broader, and pointed, 

 instead of bluntly rounded, at its anterior end ; maxillo-palatines more 

 oval or strap-like, not so shoe-shaped or hook-like, and much more 

 widely separated; ttie palatal opening between the halves of the 

 premaxillary smaller, narrower, more oval (less ovate) ; pterygoids 

 not so far sei3arated from the basisphenoid, but resting almost against 

 it for the anterior half of their length ; second primary (counting from 

 the outermost) longest, the third only a little less, the first consider- 

 ably shorter than the third and about equal to the fourth (in 

 Caprimulgus ^ the second primary is also the longest, but the third is 

 decidedly shorter, the first still a little shorter or equal, but very 

 much longer than the fourth) ; three primaries sinuate on their 

 outer webs, instead of two as in C afrimnlgus ; tail more rounded; 

 wing relatively shorter. 



The type of this genus is C aprimidgus vociferus Wilson. 



* J^f, oTj-zdc, tinea; xo^k, avis nocturna. 

 2 See Clark, Auk, vol. 18, 1901, pp. 168-169. 



^ It should be remembered that all these comparisons with Caprimulgus refer to Capri- 

 mulgus europaeus only. See p. 10. 



