158 MR. W. K. PARKER ON THE OSTEOLOGY 
development in the “ Tetraonidz,” and are enormous in the Cock of the Woods (Tetrao 
urogallus). These angular processes are similarly developed in the “ Anatinz.” 
I have not been able to find a ‘‘ coronoid ” element as a distinct piece in the chick, 
although we see it in the Ostriches, and indeed in most birds. The os hyoides is very 
elegant in all these ‘‘ Galline ;”’ the true hyoid cornua are delicate and lie in the tongue, 
their tips being cartilaginous ; there is also a basi-hyal, a uro-hyal, and the two double 
thyro-hyals: all delicate and rather feebly ossified (Pl. XXXVI. fig. 10). 
Lastly, the great anterior semicircular canals are a considerable distance from each 
other over the sides of the foramen magnum ; and yet the posterior crus of each canal 
is imbedded in the side of the corresponding superoccipital. There is no distinct 
“epiotic” in the chick; but on about the eighteenth day of incubation a small 
‘* opisthotic ’’ may be seen: it soon coalesces with the exoccipital. In Lagopus the 
columella is extremely delicate, the rod being fine, and the basal plate large and thin ; 
the rod thickens before it trifurcates, but the branches do not ossify. I have never 
seen in these, nor indeed in any other birds, any bone answering to the os orbiculare 
of Man and the superquadrate ossicle of the Lizard; nor does there appear to be any 
bone in birds answering to that small osseous segment of the periotic capsule of the 
Mammal which becomes converted into the ‘‘ pyramid,” and which appears to be a 
rudiment of that huge proximal piece of the hyoid arch of the fish, which, breaking 
away from the postfrontal, ali-temporal, and prootic regions, becomes developed into 
the hyo-mandibular. With regard to the structure of the rest of the skeleton of the 
type and subtype, it may be remarked that the differences are similar to what is 
seen in the skull. On one hand, we have coarseness of texture, with a considerable 
amount of diploé ; on the other, there is a lathy and rather tough than strong condition 
of the bones. In treating of the other groups of Gallinz, I shall have to speak of the 
skeleton both of the Fowl and of the Grouse. It may be said, however, that the 
sternum of the typical Fowl and Pheasant is exactly intermediate between that of the 
gigantic Turkey and Peacock, on one hand, and that of the Quail and Partridge 
(PI. XLI. figs. 9 & 10) on the other, and that in the gigantic forms the shortness of the 
hyposternal processes and the general characters of the entire bone closely approxi- 
mate to the conditions we find in the Brush-Turkey (Talegalla), and the Curassow (Craz). 
There is, however, one of the typical species, a dwarfish form, of which I must speak 
before passing on to the Megapods: this is the Guatemala Tree-Partridge (Dendrortyz). 
Larger than the true ‘‘ Quails,” yet possessing the same general osteological characters, 
the Dendrortyx may be said to have in its skull and face the Quail-characters highly 
exaggerated. The occipital plane is vertical and flat, the condyle bifid, the tympanic 
cavity shallow, the skull-walls thick and having a rather coarse diploé, the interorbital 
septum somewhat deficient, the bird being rather small; the temporal space is bridged 
over, as usual. The antorbitals and the rest of the lateral ethmoidal and pre-ethmoidal 
structures continue cartilaginous as in the type. The vomer and the palatines are as 
