British Fossils — Prof. Owen on Plerodactyle. 99 



also well developed. In Bhampliorhynrhua,^ on tlie contrary, the 

 hind-limbs are almost rudimentary (see Plato IV. Fig. 4), and could 

 have been but feeble organs, either for walking or climVjing, as com- 

 pared to the hind-limbs of Dimorphodon (Plate IV. Fig. 1 j. 



The skull and jaws of Dimorphodon differ remarkably from every 

 other Pterodactyle at present known. The head is large in propor- 

 tion to the trunk, not only in respect to its length, but more 

 especially in its depth, and probably also in breadth. The two 

 crania preserved in the British Museum both show the profile very 

 fairly perfect, and both exhibit the great depth of the head ; 

 " nevertheless," writes Prof. Owen, *' the shape and disposition of 

 the bones are such that, perhaps, no other known skull of a verte- 

 brate is constructed with more economy of material — with an arrange- 

 ment and connection of bones more completely adapted to combine 

 lightness with strength." 



In Bharnphorhjnchus the anterior portions of both the upper 

 and lower jaws are edentulous, and from their shape Hermann 

 Von Meyer has inferred that they were covered by horny sheaths, 

 like the beak of a bird. In DimorpJwdon, on the contrary, the 

 jaws throughout are armed with a coraVjination of laniary teeth, 

 and more closely set and smaller serial teeth in the lower jaw. 



EefeiTing to Dr. Buckland's original paper in the Geological 

 Transactions, it is extremely interesting to note that with the 

 limb-bones there are also figured two or three of the long slender 

 caudal vertebrae imbedded in osseous fibres ; these, however, were 

 regarded by Dr. Buckland as cervical. " The tail," he observes, 

 " was probably langer than in P. longirostris, and may have co- 

 operated with the legs in expanding the membrane for flight : — a 

 long and powerful tail is in strict uniformity with the character of 

 a lizard" (p. 221.) This observation seems quite prophetic, for 

 no long-tailed Pterosauria were then known. (See Eestoration, 

 PI. IV. fig. 2.) 



Professor Owen gives a careful analysis of the observations of 

 Hermann Von Meyer on the Pterodactyles of the Solenhofen stone. 

 That able naturalist and palaeontologist is, alas t now no more, but 

 his name and vast labours will be long valued by scientific men. 



Von Meyer quotes Oken's opinion, "that the skull in the 

 Pterodactyle is intermediate in character between that of the 

 chameleon and crocodile," and thus concludes : " The skull of 

 Pterodaclylus is essentially comparable only with that of Birds 

 and Saurians. The preponderating resemblance to the bird's 

 skull cannot be contested. Against this, however, is a remark- 

 able dissimilarity in certain parts which, on the other hand, ap- 

 proximates it to the type of Saurians." (Von Meyer, in Owen's 

 Mon. p. 60.) 



Professor Huxley, in various papers which he has published, 

 has demonstrated, chiefly on osteological grounds, the close afiinity 

 existing between Birds and Eeptiles. One of the most important 



^ See Illustrations to paper, by H. "Woodward, in the " Intellectual Observer," 

 Vol. ii. 1863, pp. 443-451, '" The flying Lizards of the Secondary E,ocks." 



