66 
FOSSIL EEPTILIA OF THE 
most resemblance to the Pterosaurian tympanic.^ For, besides the Lacertian freedom of 
the bone from zygomatic abutment, the tympanic in the Chameleon has not the 
longitudinal strengthening ridges, nor the process turned toward the pterygoid. 
The dentigerous mandible, like the maxilla, speaks for the Reptilian affinity of 
Pterosauria ; the distinct sockets for the teeth ally them to the higher forms of Sauria. 
In reference to the generic modification of dentition in Dimorphodon, it has been remarked 
that this early form of flying dragon seemed to have derived one feature or modification 
from the Fish, and the other from the Crocodile or Plesiosaur. ® 
The length of the neck, which is not always equal to that of the head, is due, in 
Pterosauria, rather to the length than the number of the vertebrse. Counting the axis 
with the small coalesced atlas ^ as one, I give seven cervical vertebrae to the Dimorphodon 
macronyx (PI. XX, fig. 1, c). Of these a series of four are preserved in the specimen (PI. 
XVIII, c), showing, as described, the characteristics of the Pterosaurian cervical vertebrae 
which had been determined and illustrated in a former Monograph.^ 
Cuvier,^ in his searching analysis of the evidence at his command of the osseous struc- 
ture of the Pterodactylus longirostris, concluded that the cervical vertebrae were not fewer 
than seven, as in Crocodilia and Mammalia, or not more than eight, as in Chclonia. 
Goldfuss was able to demonstrate the vertebral formula in his famous specimen of 
Pterodactylus crassirostris^ The number, ‘ seven,’ was, however, obtained by reckoning 
the atlas distinct from the axis, and the last cervical may have been relegated to the 
dorsal series. 
Quenstedt'^ shows seven cervicals in his instructive example of Pterodactylus suevicus, 
reckoning the atlas and axis as one vertebra; and this analogy I have followed in the 
restoration of Dimorphodon. 
Bhamphorhynchus Gemmingi has six cervicals, counting the coalesced atlas and axis as 
one ; but in the specimen figured by Von Meyer in his pi. ix,® there seems to be the centrum 
of a short ‘ seventh ’ cervical between the longer ‘ sixth ’ and the first (dorsal) vertebra 
supporting a long free pointed rib. It is certain that the number of cervicals does not 
exceed the latter reckoning or fall short of the first. Thus it is plain that Pterosauria 
exemplify the Crocodilian affinity in the cervical region of the vertebral column. Lacer- 
* “Dieser Knochen ist nicht wie in den Vdgeln quadratisch, sondern cylindrisch stielformig 
beschaffem. — Hierin, so wie in einingen andern Theilen, zeigt das Tliier die meiste Aehnlichkeit mit Cha- 
maeleon." — Von Meyer, op. cit., p. 16. 
2 ‘Report (Sections) of the British Association for the Advancement of Science,’ 8vo, 1858, p. 98. 
® ‘Monograph on the Fossil Reptilia of the Cretaceous Formations,’ Supplement, tPterosauria 
(1859), pp. 7 — 8, PI. I, figs. 11 — 14. 
^ Ib., p. 9 — 11, PI. IT. ‘Monograph,’ &c.. Supplement, No. Ill (1860), p. 7, PI. II, figs. 1, 
2 and 4. 
^ ‘Ossemens fossiles,’ tom. cit., p. 367. 
® “ Man zahlt 7 Halswirbel, 15 Rippenwirbel, 2 Lenden, and 2 Kreuzbeinwirbel,” loc. cit., p. 78. 
7 Op. cit., figs. 1 — 7. 
® Op. cit. 
