424 NORTH AMERICAN BIRDS. 



Three species of this gemis are described by autliors, all of them black, 

 witli wliite throat, and a luitcli of the same on each side of rump, and other- 

 wise varied with this color. Tlie type P. cayancmis is much the smallest 

 (4.70), and has the tail more deeply forked than P. melanoleuca. 



Synopsis of Species. 



P. cayanensis. GloKt^y intense black; a .-Jiipraloral spot of white; white 

 of throat transversely defined ])osteriorly. Tail deeply forked, the lateral 

 feathers excessively attenuated an<l acute. 



Wing, 4.80; middle tail-feather, 1.20, external, 2.30. Hub. Cayenne 

 and Bra;!il var. cayanensis} 



Wing, 7.30; middle tail-feather, 1.90, external, 3.60. Hah. Guateniahv. 



var. sancti-hieronym i.' 

 P. melanoleuca. Lustreless dull black ; no snpraloral white spot, but 

 instead a hoary wash ; white of throat extending back along middle of 

 abdomen to the vent. Tail moderately forked, the lateral feathers obtuse. 

 Wing, 5.75 ; middle tail-feather, 2.30, outer, 2.85. Hab. Middle Province 

 of United States, south to Guatemala. 



Panyptila melanoleuca, Baird. 



WHITE-THSOATED SWIFT. 



CypscJus melanolcucus, Baird, Pr. A. N. Se. Phil. VII, June, 1854, 118 (San Francisco 

 Mountains, N. AI.). — Cassi.v, iUiMt. 1,1855, 248. Panyptila melanoleuca, Baiko, 

 Birds N. Am. 1858, 141, pi. .wiii, f. 1. — Sci.ateb & Salvin, Ibis, 1859, 125 (Guate- 

 mala). — Sclatku, P. Z. S. 1865, 607. — Kenneuly, P. R. K. X, b, 36, pi. xviii, f. 1. 

 — Hkehmann, lb. X, c, 10. —Cooper, Orn. Cal. I, 1870, 347. 



Sp. Char. Wings very long ; tail forked ; tarsi and feet covered with feathers. 

 Black all over, except the chin, throat, middle of the belly as far as the vent, a patch 

 on each side of the rump, the edge of the outer primary, and blotches on the inner webs 

 of the median tail-feathers, near the base, which are white, as is also a band across the 

 ends of the .secondaries. Length, 5.50 ; wing, 5.50 ; tail, 2.70. 



IIar. Nevada, Utah, Colorado, Arizona, and southern Rocky Mountain.s, to Guatemala. 

 Localities : Cajon Pjuss (Cooper, Pr. Cal. Ac. 18G1, 122) ; Arizona (Coues, P. A. N. S. 1866, 

 57) ; San Diego (Cooper). 



Although there is no difference in size between Eocky Mountain and 

 Guatemalan specimens, the only two of the latter in the collection arc darker 

 colored, showing scarcely any indication of the frontal anu supraloral wnitish 

 so conspictious in most northern skins. In tlie Guatemalan female (30,837, 

 Duefias, February 13) the dusky of the lateral, and white of the medial, 

 portions of the breast blend gradually together, there not being that sharp 



> Panyptila cayanensis (Gmki,.), Cab. Hirundo cay. Gmei.in, Syst. Nat. I, 1024. Panyptila 

 cay. Cahan. Wiegm. Archiv, XlII, 345 (1847). — Sci,. P. Z. S. 1866, 606. 



* Panyptila .ianct.i-hiiToii.ymi, Sai.vi.n (P. Z. S. 1863, 190, pi. xxii ; Scr,. P. Z. S. 1866, 

 607). May be the northern form of cayanensis, which, however, we have not seen. 



