Stewart.] Cretaceous Fishes, 283 



angles with each other, and are separated by a slightly con- 

 stricted neck just in front of the scapula. The anterior portion 

 is directed slightly downward at the extremity and is very thin, 

 fragile, and it is probably owing to this fact that it is secured 

 in so few specimens. Just above the scapula the cleithrum be- 

 comes very broad and continues so to near the upper extremity, 

 when it suddenly contracts in width tOAvard the anterior border, 

 and ends in a somewhat thickened process, below which there is 

 a well-marked dentate suture for the anterior end of the precora- 

 coid. The whole of the anterior border is firmly united with the 

 precoracoid, and the external side is covered with coarse striae, 

 which radiate upward and backward from just over the scapula. 



The scapula is a rather small bone, composed of a heavy com- 

 pact portion which bears the glenoid surface and a rather thin 

 lamina of bone which extends upward along the internal side 

 of the cleithrum. The glenoid portion is united to the cleithrum 

 above by means of a well-marked undulating suture, and bears 

 three condyles, of which the uppermost is the largest, and is 

 separated from the middle one by a slight ridge. The middle 

 condyle is the smallest and is separated from the lower one by 

 a slight groove. The condyles are all convex from before back- 

 ward, the superior one very much so. Just internal to the 

 glenoid surface there is a large irregular surface which gives a 

 strong attachment to the coracoid, and also gives a partial sup- 

 port to one of the basiosts posteriorly. Just above this portion 

 the precoracoid is united by a strong suture and extends up- 

 ward as a broad bar on the internal side of the cleithrum. 



The coracoid has been figured by J I ay 17 as a broad, thin plate 

 of bone which extends forward to probably the anterior end of 

 the lower arm of the cleithrum. It is not well preserved in 

 any of our specimens, but from the portions that are present I 

 am inclined to think that it is the same bone described and fig- 

 ured by myself as a probable infraopercular. 4S It is somewhat 

 thickened where it joins the scapula and has one deep pit and a 

 portion of another for the extremities of two of the basiosts. 



47. 1. c. p. 43. 



4-. Kans. Univ. Quart., vol. VIII, p. 21, pi. XI. 



