Since the publication of my first paper upon the American forms of _Tinnunculus_,[59] a large amount of additional material has fallen under my observation; the total number of examples critically examined and compared together amounting to over three hundred and fifty skins of which I have kept a record, besides many others which have come casually to my notice. This abundant material merely confirms the views I first expressed, in the paper alluded to, regarding the number and definition of the forms; their comparative relation to each other being the only respect in which I have reason to modify my arrangement. In my first paper on the American _Tinnunculi_, three distinct species were recognized; one (_sparverius_) belonging to the whole of Continental America and the Lesser Antilles, one (_leucophrys_, Ridgway) to Cuba and Hayti, and one (_sparveroides_, Vig.) peculiar to Cuba. The first is one modified in different climatic regions into several geographical races, as follows: Var. _sparverius_, L., North and Middle America, exclusive of the gulf and Caribbean coast region; var. _isabellinus_, Swains., the eastern coast region of Tropical America, from Guiana to Florida; var. _dominicensis_, Gmel. (Lesser Antilles); var. _australis_, Ridgw. (South America in general); and var. _cinnamominus_, Swains. (Chile and Western Brazil). That each of these races is well characterized, the evidence of a series abundantly sufficient to determine this point enables me to assert without reserve; for I find in each instance that the characters diagnosed in my synopsis hold good as well with a large series as with a few specimens. The following synopsis, essentially the same as that before published, may, to most persons, explain satisfactorily my reasons for recognizing so many races of _T. sparverius_,—a proceeding which, I am sorry to say, does not meet with favor with all ornithologists.[60] Though there are at the present time three well-characterized or permanently differentiated species of _Tinnunculus_ on the American continent, yet it is, to my mind, certain that these have all descended from a common ancestral stock, for evidence in proof of this is found in many specimens which I consider at least strongly “suggestive” of this fact; some specimens of var. _isabellinus_ from Florida having blue feathers interspersed over the rump, thereby showing an approximation toward the uniformly blue upper surface of the adult male of _T. sparveroides_ of the neighboring island of Cuba; while in the latter bird the embryonic plumage of the male is very similar to the permanent condition of the male of _sparverius_. Synopsis of the American Species. =A.= Back always entirely rufous (with or without black bars.) Lower parts white, or only tinged with ochraceous; front and auriculars distinctly whitish.