1889.] MR. W. K. PARKER ON STEATORNIS CARIPENSIS. 163 
Classification of Birds was being written, I pointed out to Professor 
Huxley that even in the Gallinaceous tribes, which are, more than 
any other birds, most distinctively ‘‘ Schizognathous,” the larger 
Curassows, e.g. Crax globicera, are “ Desmognathous.” 
I have since that time discovered that Dicholophus is directly 
Desmognathous'. 
If we then bind up together some two dozen families of arboreal 
birds of the higher, but not highest kinds, and call them “ Coccy- 
gomorphe,” we must use the palatal character for just what it is 
worth and no more. If all these troops are to march under the 
Huxleyan standard, then we shall have the following palatal cha- 
racters in this mixed multitude of birds :— 
ScurzoGnatTuism.—Trochilide, Trogonidz, Caprimulgide (part.). 
EGITHOGNATHISM.—Cypselidee. 
DrsmMocNnatuIsm.—(a. Indirect) .—Coliide. 
(6. Imperfect direct).—Capitonidee. 
(ce. Perfect direct). — Rhamphastide and 
many others. 
(d. Double).—Bucerotidze (part.), Steator- 
nithidee, Podargidee. 
SAUROGNATHISM *.—Picidee, Yungide. 
So, again, with regard to another of the deep morphological cha- 
racters, namely, the arrest or development of the “ hasipterygoids ”’; 
in this character we have the extremest difference, for Steatornis is 
almost Struthious in this respect, and Cuculus (amongst others) has 
these parts aborted as much as in the Passeres, in which they very 
seldom show a trace in the adult. 
Another deep and diagnostic character is the peculiar articulation of 
the centra of the vertebree, between the axis and the sacrum’. This, 
as a rule, is what is called eylindroidal by Prof. Huxley, and hetero- 
ceelous by the American ornithologists. “Now it has long been known 
that many Water and Wading birds have their thoracic or dorsal ver- 
tebree of the archaic type—like those of ancient reptiles, they are 
opisthocelous. But I long ago showed that Parrots have the same 
structure, combined with an anticipation of the Mammalian centrum, 
namely with terminal epiphyses. But more lately I have discovered 
that the dorsals of Séeatornis are opisthoccelous also. This fact has 
softened down my objection to putting the Parrots along with the 
other Zygodactyles and their Syndactyle relatives ; they are not more 
isolated than the Humming-birds and the Swifts. The manner in 
* In my paper on the Bird’s Skull, Linn. Trans. new series, Zool. vol. i. 
p. 129, pl. xxv., I have described the palate of this bird as being imperfectly 
desmognathous ; the bony union of the “ maxillo-palatine plates” is, however, 
perfect in my specimen. 
* Strictly speaking the Aigithognathous and the Saurognathous palates are 
merely varieties of the Schizognathous type; that reduces the whole thing to 
two main kinds—the Schizognathous and the Desmognathous; the “ Dro- 
mzognathous” condition is merely a retention in the adult of an early embryonic 
stage. 
% Proc. Roy. Soe, 1888, pp. 465-482. 
