590 



BRITISH FOSSIL REPTILES. 



Fig. 8. 



Tibia, Celiomurus longus , -j'jth iiat. size. (Phps., part of diagr. cix, p. 282.) 



As Profe3.sor Phillips remarks, " the terminal surfaces are strongly marked by the 



pitted adherence of cartilage, which gives the appearance of deficient 



epiphyses." * 



In a full-grown Monitor niloticus the distal epiphysis, which affords the articular 



* P. 282-3. He adopts an idea tliat the convex part of the anterior surface of the distal portion of 

 the shaft of the tibia in the Crocodile is the honiologue of the ascending process of the astragalus of 

 Megalosaurus, but "separated from its base and anchylosed to the tibia; while in A[egalosaurus the con- 

 nection remains, and the ascending process is not joined by synostosis to tlie tibia" (op. eit., p. 283). 

 Scelidosaurus instructively exemplifies the homology of the distal epiphysis of the tibia in Dinosaurs with 

 that in the Monitor and the Bird, and demonstrates the separate existence of the bone answering to the 

 astragalus, &c., in both Crocodiles and Lizards, but which is not ossified in the tarsus of Birds (p. 499, 

 cut, fig. 4). 



