Hybridity in Animals. 208 
Art. XXIl.—Hybridity in Animals, considered in reference to 
the question of the Unity of the Human Species; by Samvet 
EoRGE Morron, M. D. 
(Continued from p. 50, this volume.) 
Part I.—BIRDS. 
__ Gallinaceous Hybrids.—The variation of size, form and 
lumage, so remarkable among the different breeds of domestic 
owls, has been usually attributed to the action of physical agents 
on a single, original species. This supposition however, is now 
found to be untenable; for the best ornithologists, and_ those, 
too, who have no view to collateral gempralization, have succeed- 
ed in tracing this family of birds to, at least, ten different species. 
Without appealing to unnecessary details it is sufficient to ob- 
serve, that independently of certain admitted changes as the re- 
sult of domestication, these birds are in far greater degree modi- 
fied by the power possessed by their several species, (so far, at 
least, as the experiment has been extended,) of mingling with 
each other and producing a fertile hybrid progeny. Hence, in a 
great measure, those interminable varieties of exterior form, size 
and color now ever amiliar. . bil atl 
The Gallus ecaudatus (tail-less fowl) has been triumphantly 
quoted as an evidence of the power of climate and locality to 
produce changes, not only of plumage, but of anatomical conform- 
ation. 'This bird is deficient in the last dorsal vertebrae, and con- 
Alectors of ornithologists,—among which the very same in- 
Apres tomer ee ee 
‘ * We have been at some pains to ascertain the specific names of the several 
original gallinaceous birds; yet without presuming that ornithologists have de- 
Scribed Il that exist, we append a list of such as are already known: Gallus 
twa; G. eneus; G. Anstrutheri; ye 
3 G.morio; G. lanatus 
— which may, for the present, be regarded us apocryphal, I 
casure of examining five of these original species, contained in the 
the Academy of Natural Sciences of Philadelphia. 
t Griffith's Cuvier, viii, pp. 19, 21, 173.—Temminck, as quoted in the same work. 
