20 FOSSIL REPTILIA OF THE 



length of the leg (' cnemion') is 1 foot; the length of the thigh is 1 foot 4 inches; 

 consequently the total length of the hind limb is 3 feet 5 inches ; and, allowing for 

 the tibro-cartilaginous matter of the joints and the terminal claws, the limb may 

 have been 3 feet 8 inches long in the recent animal. 



The femur equals the length of about seven co-articulated dorsal vertebra?, and, 

 with the leg, manifests longer proportions to the body than in the Crocodilia ; but 

 the foot presents shorter and broader proportions although it has the same number 

 of toes. Scelidosaurus, however, differs from Teleosaufus and modern Crocodilia 

 in retaining the ungual phalanx of the fourth toe, as in modern lizards (Tab. XI, 

 fig. 3,i v) ; although it differs from these and resembles the Crocodiles in the non- 

 development of the fifth toe. The interesting evidence of this intermediate 

 relationship afforded by the bones of the hind foot, as by some other parts of the 

 skeleton, is illustrated by the outline figures of the skeleton of the hind foot 

 (Tab. XI) in Varanus, fig. 3, in Crocodilus, fig. 4, and as similarly restored in 

 Scelidosaurus, fig. 2. 



In the same plate is figured, of half the natural size, the bones of the right 

 hind foot of the skeleton of the Scelidosaur which has yielded the subjects of the 

 present Monograph ; showing the effects of pressure in fracturing and partially 

 dislocating the metatarsal segment, after all the joints of the toes had been 

 cemented by the surrounding hardened matrix in their respective varied numbers 

 and co-adjustment in each toe. 



Dermo-skeleton. 



The bones belonging to this system were extensively developed in Scelido- 

 saurus, and are for the most part of a massive character. They have been much 

 displaced in the present specimen, partly during the decomposition of the carcass, 

 and partly by subsequent pressure due to movements of the imbedding stratum; 

 but retain their most intelligible natural relations to the endo-skeleton in the caudal 

 region : in which part, therefore, I shall begin their description, as they were 

 found, on exposing the vertebral characters on the left side, from the end of 

 the tail forwards; and were either removed, or left in situ, as the case required. 



At the thirty-first caudal vertebra, for example, there was attached to the back 

 part of the neural arch, and pressed rather obliquely to the left side, an elongated 

 triedral dermal bone, with the narrowest side or surface forming the base, and 

 the two broader or larger lateral surfaces converging at an acute angle to an 

 upper ridge. Much of this ridge on the fore part of the bone had been broken 

 away in the original exposure of the specimen ; the length of what remained was 

 1 inch 2 lines, with a basal breadth of 6 lines. The sides of the bone seemed as if 



