nil 



.ii'jn\if PROONE. % :> 



■*?■'"■ 



2Sl 



the back ; chin, throat, jugulutn, and sides of head (below the tentre of ten 

 eye) neck and body, with in8i()e of wings, gniyish-brown, witliout gIo«s or 

 lustre (as in Cottjle ri/iuria'), rather lighter along the median line. Rest of 

 under parla dull white, not very sharply defined, passing behind into pure 

 white on the anal region and crissuni — the latter having the shafts of the 

 longer feathers dusky, in conirast wHh the snowy white of the plume. A 

 loiicealed white stripe on the sides under the wings, as in other Proyne. Tibia 

 gray, the feathers tipped with whitish. 



The female (30,717) is -luite similar, with much less gloss above, the white 

 of the belly apparently passing further forward, and still less sharply defined; 

 the throat a little lighter. 



(i\o. 3(1,718, -£, Guatemala.) Total length, 6.30; wing, 5.10; tail, 2.70; 

 perpendicular depth of fork, .53 ; difference between 1st and 9th primary, 

 2.55; length of bill from forehead, .50, from nostril, .28, along gape, .84; 

 width of gape, .62 ; tarsus, .49 ; middle toe and claw, .73 ; claw alone, .23 ; 

 bind toe and claw, .46 ; claw alone, .22. , 



This Mexican and Central American species has generally been 

 considered to be identical with the West Indian P. dominicensis, 

 but a comparison of large series of specimens shows considerable 

 (lifforences. It is decidedly smaller, and the depth of fork of tail 

 only two-thirds as great. As to color, none of the specimens before 

 me exhibit any trace, on the under surface of the body, ot the 

 glossy steel blue of the back, found in males of domit}iccni<is ; in 

 this respect resembling fenmles and immature males of the latter 

 species. From these, however, it may be distinguished by smaller 

 size — even in the males — and by having the shafts of the longer 

 erissal feathers dusky, instead of being pure white. T!ie white of 

 the belly is less abruptly defined against the gray of the breast 

 (whieli is darker also), and apparently occupies a wider space. 



Tiie male bird (No. 30,718), the measurements of which I have 

 piven, appears to have a disproportionately short foot. In No. 

 30,Tn, supposed female, from Ducfias, the dimensions of the leg are 

 as follows: Tarsus, .56 ; middle toe and claw, .81 ; claw alone, .27 ; 

 hind toe and ciavv, .51 ; claw alone, .26, or nearly the size of P. 

 ah/h's with longer middle toe and claw. Other specimens are inter- 

 mediate somewhat in this respect. It may be that the differences 

 indicate a second species, but I cannot define it from the materials 

 at my command. The only other difference I note is a greener or 

 less piiri)le gloss to thr back. 



It is barely possible that fully adult males of this species may- 

 have steel blue throats, as in true domivicenHis, although I find no 

 aiiusiou to the fact in any description. Even in this case, however, 

 the smaller size, less deeply forked tail, and dusky shafts of the longer 

 erissal feathers will distinguish them. 



