Allied to the last in tints of coloration, and apparently a direct offshoot from it, is the _dominicensis_ of Gmelin (based upon description by Brisson), which inhabits the Lesser Antilles, from Trinidad northward to Porto Rico. Although I consider this (var. _dominicensis_) as a modified form of the var. _isabellinus_, yet it is the one of all the varieties referrible to _sparverius_ which deviates most widely from the typical or original style. The characters of this are, tints those of var. _isabellinus_, but, in addition, the tail has numerous more or less complete black bands, while those of the back and scapulars are very broad and numerous; also, the crown has a decided rufous patch; the bill, too, is larger than in any other American member of the genus. A style of considerable uniformity spreads over the whole of South America, including both coasts, from Bogota to the Parana, excepting the northeastern coast region, before mentioned as inhabited by the var. _isabellinus_. It differs from all the other styles, except the _cinnamominus_ of Chile, in having the lower parts continuously dull white, any ochraceous tinge being scarcely perceptible; there is seldom a trace of rufous on the crown, which has the light bluish tint seen in var. _sparverius_, and the black zone of the tail is scarcely more than half as wide as in the northern races. In size, also, it somewhat exceeds the others. Swainson named this “_Falco gracilis_”; but the _F._ (_Tinnunculus_) _gracilis_ of Lesson being a different species, and the name as applied to it of prior date, I have bestowed upon the present bird the name var. _australis_. In Chile and Brazil (Western ?) we find a form resembling the last in some respects, but differing in points of almost specific value. It differs from all the other American members of the genus in having the tail continuously rufous to the extreme tip, the black zone being considerably narrower than the terminal rufous, the lateral tail-feather immaculate rufous, etc. The grayish of the head is much darker and more slaty than in the var. _australis_. This is, without doubt, the _Falco cinnamominus_ of Swainson, the specimens in the collection corresponding exactly with the description by that author. The rufous patch on the crown must not be too much considered, as it is of all characters perhaps the most treacherous, though its presence or absence is in a measure characteristic of the several varieties. Neither does the exact number of spots on the lateral tail-feather prove sufficiently constant to serve as a character in which the least reliance can be placed, though Swainson attaches considerable value to it. I have found that, besides varying almost with the individual, in some specimens the feathers of opposite sides did not correspond. About two hundred and fifty specimens form the basis of the following synopsis. =A.= Tail tipped with white; outer tail-feathers (one or more) variegated.