WiLLISTOK: KANSAS PTERODACIVI.S. 



of the leg, so that it was an easy 

 matter to amplify the pelvis to a 

 size corresponding with that of th.e 

 remaining bones. 



The ilium has a long anterior 

 projection, moderately expanded 

 distally. Posteriorly, it extends 

 more stoutly upward and back- 

 ward from the acetabulum, to 

 form a close union with three 

 vertebrae, terminating in a stout, styliform tuberosity 

 on either side of the base of the tail. If, as Seeley 

 tiiinks, the pubis and ischium are conjoined, they are 

 thoroughly co-ossilied throughout, forming a broad, 

 antero-posterior plate, whicli is narrowed to a sym- 

 physis about one inch in length in medium-sized 

 species. Projecting downward and forward, about 

 midway between the acetabulum and symphysis, there 

 is a moderately thickened, angular projection, evi- 

 dently tipped with cartilage in life. It is evident 

 tiiat the pubis (or prepubis?) was attached to this 

 jjrocess, and I have so restored the pelvis. A little 

 below the acetabulum, and just before the middle of 

 the conjoined plate, is the oval, antero-posterior 

 pubic foramen. (^n the border of the ischium 

 behind, a little above the symphysis, there is a second 

 tuberosity, larger and stouter than the pubic one. 

 Between this tuberosity and the iliac tuberosity, 

 directly above, there is a large, deep, sciatic notch. 

 These thickened projections seem to indicate that 

 the animal in life was in the habit of resting upon 

 these parts, a supposition further helped by the 

 weakness of the legs, and by the structure of the 

 femur. The co-ossified pubic bones are very thin, 

 probably U-shaped in life, witli an anterior projection 

 for the attachment of a ventral rib, and with a 

 slightly expanded symphysis. A figure of them 

 is given in my previous paper (this journal, I, p. 4,). 

 I confess myself undecided as to whether the bone 

 really represents the pubis or the prepubis. 



The femur is a moderately stout bone, considerably 

 shorter than the tibia, considerably curved, with a 

 slender neck, set at only a slight angle with the shaft, 



