16 



The coossified pelvfc elements resemble, in their compression below, the 

 corresponding parts in the Anura. The ilia are, however, shorter and 

 worn as in the Urodela. They are flat, and stand at right angles to the 

 line of the ischiopubic symphysis. There is an open concavity of their 

 inferior posterior free border, and a facet-bearing elevation on the inferior 

 border, or that entering into the formation of the acetabulum. The latter 

 is large and half as loDg auain as deep. The anterior and posterior borders 

 of the pelvis descend regularly to the inferior edge, forming with it a trian- 

 gle. The ischiadic or posterior border is but little thickened ; the anterior, 

 or pubic is flat in front and presents a reverted edge outwards. This ex- 

 pands prominently where it is joined by a ridge which bounds the acetabu- 

 lum below ; it there contracts to an inferior apex. Beneath the anterior 

 point of the acetabulum it is pierced by the usual foramen, which issues on 

 the inner edge of the anterior face, just above the symphysis. 



The humeral bones of this genus I probably possess ; but I have several 

 forms between which I am not able to decide. They are in general like 

 those of the Pelycosauria, but differ from them in not having an enclosed 

 supracondylar arterial foramen, but only the buttresses of its enclosing 

 arch. Two such forms I have already described,* and a third has been 

 obtained from the French Permian by Professor Gaudry. One quite 

 similar to the latter I have since obtained from Texas. Not having been 

 able at first to determine the proper reference of these humeri, I suggested 

 to Prof. Gaudry that his humerus belongs to one of the Pelycosauria, and 

 he accordingly described it as EucMvosaurus rochei.\ I now think that 

 there is greater reason for believing that it belongs to a species of the same 

 group as Eryops and Actinodon. 



In all these humeri the extremities are expanded in different planes, and 

 the shaft contracted. The articular surface of the proximal extremity is 

 band like and passes obliquely from one side to the other as in the Pelyco- 

 sauria. The condyles are large, consisting of a globular portion and a de- 

 pressed trochlea without ridges at one side of it. 



The femora are very different from the humeri, but in much the same 

 way as in the corresponding bones of existing Batrachia. There are 

 no condyles at either extremity, but outlines of such, enclosing roughened 

 surfaces. These look as though the bases of attachment of cartilaginous 

 caps or epiphyses. The proximal extremity is convex, and is extended in 

 one direction. One border, the anterior, is regularly gently convex ; the 

 opposite arc is strongly convex near one end only. The articular face is 

 in two planes, one larger than the other. The trochanteric fossa is at first 

 shallow, and occupies the entire wid:h of the bone, it narrows with the 

 shaft downwards and the borders rise, one more than the other. The two 

 join in a strong protuberance, which looks directly backwards, and may be 

 called for the present the third trochanter. The shaft is keeled below and 

 in continuation of the trochanter, to where it expands for the distal articu- 



* Paleontol. Bulletin, 29, 1878, p. 529. 

 t Bulletin Soc. Geol. France, Dec , 1878. 



