SHUFELDT. ] OSTEOLOGY OF THE CATHARTIDA. 743 
binal coming from within; this can hardly be said of C. atrata, as the 
latter bone in this Vulture is so far removed backwards into the rhinal 
cavity. The forms of the nostrils among the Cathartide can be better 
studied from the various figures in the plates than from any detailed 
description we might give, however elaborate it might be. Thus far we 
have spoken of the irregular wing-like bone found in the rhinal chamber 
of any of the Cathartide as the ethmo-turbinal, and it certainly fulfills 
the functions of that bone as found in others of the class, where it occurs. 
Not having the young of any of the Vultures at hand, however, we can- 
not say that its representative here ossifies as a separate segment, 
though to all appearances it does. 
Huxley seems to refer to it when he says: ‘‘In the genera Cathartes 
and Sarcorhamphus the cleft between the thin and scroll-like maxillo- 
palatines is very deep and wide, and the ossification of the septum is 
small in extent, and only forms a sort of bridge over the deep and wide 
valley between the maxillo palatines.”—(Classification of Birds, Proc. 
Zool. Soc. Lond., 1867, pp. 441.) 
It consists essentially of a horizontal plate of bone extending across 
the nasal cavity to the rear of the nostrils, and about half way between 
the roof of the rhinal chamber and the palatine plates beneath. Mesi- 
ally it throws out a sharp process in front (C. awra), which curls up in 
Pseudogryphus (Plate XVI, fig. 106), and another plate, that reaches to 
the roof of the cavity, where it extends backwards to meet the ethmoid 
in C. aura and C. atrata, and in all of the species spreads out more or 
less laterally, thus forming a strong abutment above, while it divides 
the space into two, that by the curling edges of the plates appear like 
true nostrils within. 
The horizontal plate blends with the inferior borders of the external 
nasal orifices, and at their posterior peripheries throws up another brace, 
forming a foramen at these points in Pseudogryphus (fig. 106), and in 
the other species, but not so well marked (figs. 116,118). On either 
side below the horizontal plate, lateral wings are developed, that curl 
inwards and backwards, reaching forward to be inserted with the pala- 
tines, showing an elliptical foramen in their sides just before arriving at 
the articulation. No doubt but this irregular ossification that we have 
been describing affords additional surface, wben it is covered with the 
nasal mucus membrane, for the ramification of the nasal nerves. We 
have in our possession a specimen of a skull from Catharista atrata that 
shows extensive and distinctive necrosis of this region, the infraorbital 
bars being destroyed for their anterior thirds, with a terrible loss of 
structure to the ethmoid and lacrymals and the palatine plates beneath. 
Can we account for this state of affairs by saying that it is due to the 
entrance of putrid matters while feeding upon carrion through the 
apertures in these ethmo-turbinals? We believe that the disease in this 
Vulture before us must have eventually resulted initsdeath. Itmay be 
the cause of death among many of its kind, and, if so, would be another 
cause for the decrease in birds, and constitute an item to be taken in 
connection with Henshaw’s interesting treatment of this subject. (Nutt. 
Ornith. Bull., Oct. 1881, pp. 189.) We would add that on the under side 
of the horizontal plate of the ethmo-turbinal we always find little pits 
existing, the only exception to the rule being, in the material we have— 
the cranium of Pseudogryphus. They are grouped without any particu- 
lar regard to any special arrangement, varying in specimens of the same 
species. 
The elevation existing immediately to the rear of the fronto-maxillary 
articulation has already been alluded to as a feature of the superior 
