ATTICORA. 309 



in having the toes more deeply cleft — the basal joint of the median 

 being free at its extremity on the outer side, instead of being adhe- 

 rent to the middle, or even the end of the middle joint. From Petro- 

 chelidon it differs in the longer tarsi, which equal the middle toe 

 and half its claw, not the middle toe alone ; less completely feathered 

 tarsi at upper end ; and in wanting the bristles in the chin and at 

 base of bill above, which are soft and smooth. While the nostrils 

 in Petrochelidon appear in the dried skin to be entirely without 

 membrane, in Pygochelidon they are bordered behind and internally 

 for a short distance, without, however, being overhung. 



Synopsis of Species. 

 Above and on crissum uniform lustrous blue-black. Beneath 

 white ; the feathers of chin and throat dark plumbeous at 

 base. 



Breast with a black pectoral baud. Feathers of back 

 scarcely white towards their middle portion. Cris- 

 sum entirely black ....... melanoleuca. 



Breast without pectoral band. Feathers of* upper back 

 white in middle. Crissum with all feathers entirely 

 black ......... cyanoleuca. 



(Var. montana with larger bill.) 



Breast without band. Crissum white towards anus ; long 

 feathers only black, and towards their tips. Feathers 

 of upper part of back ash-colored, not white in middle patagonica. 

 Above and on crissum greenish-black. Beneath dark ashy ; the 

 feathers of chin and throat plumbeous at base. 



Feathers of upper part of back cinereous, not whitish in 



the middle .... ... murina. 



Atticora cyanoleuca. 



Hiriuulo cyanoleuca, Vieill. Nouv. Diet. XIV, 549, and Encycl. Meth. 



1823, 521 (based on Golondrina de la timoneles negros, Azara, Apunt. 



Pajaros Par. II, 1805, 508).— ^m'cora c. Cab. Mus. Hein. 1850,47. 



— Bdrm. Uebers. Ill, 1857, 146.— Ib. La Plata Reise, II, 1861, 479 



(very common in the La Plata country ; nests under eaves and 



roofs of houses). 

 Hirundo inelampyga, Light. Verz. 1823, 57 (Bahia). 

 Hirundo minuta, Max. Beit. Ill, 369.— -Temm. PL Col. 209, fig. 1. 

 Hah. La Plata basin ? Brazil. 



(No. 35,050.) Above and on sides of head and reck to line of gape, steel 

 blue, including tail- and lesser wing coverts, as well as a patch on side of 

 breast; wings and tail feathers dark blackish-brown, with faint gloss. 

 Feathers of hind neck and interscapulum with concealed white in their middle 

 portion. Beneath white, all the feathers blackish plumbeous at the base, ex- 



