My 
322 Mr. H. Seeley on the Avian Affinities of Pterodactyles. 
dactylus longirostris ; but in the figures of P. crassirostris, P. 
longicollum, and P. Kochi it appears to be a free bone articulated 
to the squamosal and petrosal region of the skull and with the 
lower jaw. This is the case neither with Chelonians nor Croco- 
diles, and is only in a certain sense found in lizards and serpents ; 
while, on the contrary, it is characteristic of the whole class of 
birds. The form of the bone is certaimly not more Lacertian 
than Avian, while its direct attachment to the bone of the brain- 
case finds no parallel among lizards, but is exactly paralleled in 
all birds. 
Cuvier then goes on to say, “Ce n’étoit pas non plus un 
oiseau, quoiqu’il eit été rapporté aux oiseaux palmipédes par 
un grand naturaliste.’ Which position he supports as fol- 
lows :— 
(1) “Un oiseau auroit des cétes plus larges, et munies cha- 
cune d’une apophyse récurrente* ; son métatarse n’auroit formé 
qwun seul os, et n’auroit pas été composé d’autant d’os qu'il a 
de doigts.” 
These, though they may not be characters which are those of 
birds, are certainly not eminently reptilian. The elongated 
form of the tarsals im birds is peculiar, but quite functional, as 
may be seen among the penguins, where, when the so-called 
tarso-metatarsal bone is no longer erect, it becomes much 
shorter, and is nearly separated into three distinct bones. And 
it would be premature to assert that this tarsus has no analogue 
in the Cretaceous Pterodactyles. 
(2) “Son aile’ n’auroit eu que trois divisions aprés l’avant- 
bras, et non pas cing comme celle-ci.” 
This is a difference of detail only. The creatures have wings, 
and they are formed on the same general plan as those of birds. 
Most birds have two phalanges in the long finger, though some 
have three. One Pterodactyle is described as having only two 
phalanges in the wing-finger, while most of them appear to have 
four phalanges, and others but three. But im birds the longest 
finger appears to be the middle one, whereas in Pterodactyles it 
is the outermost one. This adds nothing to its supposed repti- 
lian characters. 
(3) “Son bassin auroit eu une toute autre étendue, et sa 
queue osseuse un toute autre forme; elle seroit élargie, et non 
pas gréle et conique.” 
I am not aware of any evidence tending to show that the 
pelvis of Pterodactyles. was materially different from that of 
some birds. And the discovery of a long-tailed bird like the 
* This is shown in other specimens figured since, and in the specimen 
from Stonesfield, in the Oxford Museum. 
