xi. MEGALOSAURUSHIND LIMB. 213 



posterior or ischial protuberance o- 8 in. long, the pubic protuberance 

 of very small extent. The anterior part runs out into an oval 

 blade, externally plane, internally bearing a high median crest. 

 Over the acetabulum rises a thin broad plate with two large ex- 

 ternal ridges directed to two excurrent prominences. The internal 

 surface of the broad plate is nearly plane, and marked by attach- 

 ment of vertebrae. The acetabulum is somewhat oblique, half oval 

 in outline, and quite open below. 



It more resembles the ilium of iguanodon than of megalosaurus. 

 Perhaps, however, it may be thought to be the bone of a young 

 megalosaur, of one or other of two species indicated by the scapulae, 

 because another specimen about four times as large presents some 

 trace of a corresponding form. The dotted outline in the diagram 

 represents the change which must have occurred in the course of 

 growth, if this conjecture be allowed. The outline of the specimen 

 depends on Dr. Buckland's apparently careful completion with 

 plaster, and it is possible that in the depth of the undulations there 

 may be some error. The old specimens differ somewhat in outline. 



The femur is in general of a crocodilian type. The length of 

 the longest complete specimen at Oxford is 33-5 inches f . 



It is more curved than in iguanodon, but not nearly so much 

 as in teleosanrus and steneosaurus. The head is more spheroidal 

 than in crocodile, and less impressed laterally ; it has a faintly- 

 marked flattened or concave transverse space or neck, like ceteo- 

 saurus, and projects forwards and inwards more from the general 

 line of the bone than in crocodiles, teleosaurus, and steneosaurus. 

 The great trochanter rises into a large free process, much more 

 prominent than in ceteosaurus, but less styliform than in iguanodon. 

 On the inner edge, about one-third down the bone, the lesser 

 trochanter rises in a prominent crest about six inches in length. 



The condyles are recurved and separated by a deep hollow 

 behind; and they occupy, in the largest specimen, a breadth of 8-4 

 inches ; on the outside is a sort of pulley mark for the head of the 

 fibula. 



f We possess other large femoral bones ; one, incomplete at the head, must have 

 reached thirty-six inches ; a third, of which the middle part is lost, is of much greater 

 size, so as to be computed at forty-two inches when perfect. The former was found 

 in 1869 at Enslow rocks with ceteosaurus. The latter may have been obtained from 

 the same locality ; it seems not unlikely to be of a different genus, judging from the 

 extremities only. 



