1S93J Meakns on the American Spairoxv Jla-a'ks. 253 



b. Vertex always (?) rufous; tail of male crossed b_v numerous black 

 bars; rump and anterior portion of back transversely barred or spotted 

 with black; breast and sides thickly spotted with large black spots. 

 2. t'alco caribbiP.arum. Male: Top of head dark bluish plumbeous, 

 the feathers (including those of the rusty vertex) streaked with black 

 centrally ; wings dark bluish plumbeous, very heavily spotted with 

 black; entire rufous surface heavily barred with black. Female: 

 Black bars of tail broader than the castaneous rufous interspaces; 

 spots of under surface black, many of them cordate. 

 Habitat. — Lesser Antilles. 

 B. Two distinct color phases. Front and auriculais dusky ; back entire- 

 Iv plumbeous in the male (dark ]ihase) ; with broad while frontal and 

 superciliary stripes ; under surface of quills white, merely serrated vvith 

 duskv along the terminal portion of the shaft (light phase). 

 i/-^3. Falco domincensis. Male (dark phase) : Above, dark plumbe- 

 ous, except the tail, which is as in sparverius. Below, deep rufous, 

 with a wash of plumbeous across the jugulum, and the throat grayish 

 white. Inner webs of quills slaty, crossed by indistinct dusky bars. 

 There is sometimes a trace of rufous in the plumbeous of crown. 

 Female (dark phase): Top of head slate-gray; upper parts rufous 

 brown, banded with dull black; underparts, including lining of 

 wings, castaneous rufous ; inner webs of primaries dull grayish ru- 

 fous, with transverse cloudings of dusky. Male (light phase) : Above 

 rufous, as in sparverius, but with little transverse spotting of black on 

 scapulars; crown and wings bluish gray, the former usually without 

 a rusty centre; a conspicuous white superciliary stripe, and front 

 broadly white; 'moustache' across cheeks indistinct or obsolete. 

 Below, immaculate white, the breast stained with a delicate shade of 

 salmon-rufous. Female (light phase) : Above similar to the dark 

 phase, but with crown bluer, showing a patch of rufous. Below 

 buffy white or very pale rufous, finely spotted or streaked with pale 

 rusty brown ; throat white. 

 Habitat. — West Indies, (Cuba, Hayti, San Domingo, and Porto Rico), 

 casually to southern Florida (.''). 



Before discussing the geographical races and incipient forms 

 of the single continental species, depending on locality, it will be 

 well to consider the variations, in all these species, which depend 

 upon sex, age, and season. 



DimorpJiism is confined, so far as known in this group, to the West 

 Indian Sparrow Hawk (^Falco dominicensis). In this species there is a 

 light phase which quite closely resembles typical sparverius of the east- 

 ern United States, but is whiter, with some of the dark markings reduced 

 or obsolete, and the colors finer and brighter, and a dark phase in which 

 the markings are intensified, the rufous of the upper surface, except the 



