CRETACEOUS REPTILES. 401 
in size the raven or cormorant have been discovered ; but no satisfactory deter- 
mination has yet been made of any larger species: the only unequivocal examples 
from the chalk of Kent that [ have hitherto inspected, do not exceed in size those 
of the Pterodactylus macronyx of the Oxford oolite. As the marine lizards called 
Plesiosaurus and Polyptychodon are supposed to have frequented estuaries, or to 
have swum near the shore, and as the Pterodactylus cannot be supposed to have 
flown far out to sea, the discovery of their remains in the chalk indicates the 
proximity of that formation to the land: and it may be remembered that the 
Iguanodon has been discovered in one division of the Cretaceous group. 
Species. Pler. conirostris, Owen. (Tab. XXXVIII. figs. 4, 5, 6 & 7.) 
The specimens of the anterior part of the upper and lower jaws of a Pterodac- 
tyle (Tab. XX XVIII. figs. 4 & 5), and of the conjoined extremities of the scapula 
and coracoid (fig. 6), both from Burham chalk-pit in Kent; and the portion of 
one of the long bones of the wing (metacarpus of fifth digit, fig. 7), from a 
chalk-pit at Halling in the same county, have previously been figured in the 
‘Quarterly Geological Journal,’ vel. ii. pl. 1, and are there referred to a species 
which Mr. Bowerbank states that he has described (ib. p. 8), and which he pro- 
poses to call Pterodactylus giganteus. The figures with which Mr. Dixon’s plate 
is illustrated are originals of the natural size, from the specimens cited. That 
of the fractured scapular arch (fig. 6) corresponds in size with the same part in 
the Pterodactylus (Ramphorhynchus) Gemmingi, Von Meyer* : the length of the 
head of the Pter. Gemmingi, from the nasal aperture to the end of the beak, is 7 
centimeters or 2 inches 9 lines ; the length of the same part in the cranium from 
the chalk (fig. 6) is 5 centimeters or 2 inches; but the Pterodactylus Gemmingi 
belongs to the section of the Pterosauria with long and slender beaks. In the 
Pterodactylus macronyx found in the lias of Lyme Regis, and now in the British 
Museum, the scapular arch rather exceeds in size that from the chalk of Kent 
figured in Tab. XX XVIII. fig. 6. The metacarpal bone of the fifth or elongated 
digit of the Pterodactylus Bucklandi, from Stonesfield, now in the museum of the 
Ear] of Enniskillen, exceeds in size the largest of those from the chalk figured in 
the ‘ Quarterly Geological Journal,’ vol. ii. pl. 1. fig. 6, and in Tab. XXXVIII. 
fig. 7 of the present work: at the same time it is to be observed, that this bone, 
as well as the scapular arch (fig. 6), accords in proportion with the jaws (figs. 4 
& 5), and together, if of a full-grown individual, indicate the inferiority of size 
* Palewontographica, 4to, 1846, taf. v. 
