82 ICHTHTOPTERYGIA. 



32679 . The right humerus, wanting the radial angle of the distal 

 extremity ; from Curcy. This specimen was probably 

 associated with some of the preceding specimens. Although 

 the proximal extremity has the general contour of the 

 same part in I. communis, the shaft is relatively longer 

 and more curved, and the ventral surface is more concave. 



Tesson Collection. 



32692. An imperfect quadrate ; from Curcy. Same history. 



32694. The centrum of an anterior caudal vertebra, probably 

 belonging to this species ; from the Upper Lias of Cani- 

 eres de Landes (Calvados). This specimen indicates a 

 considerably larger individual than those to which the 

 preceding Normandy specimens belonged ; it agrees with 

 other vertebrae of the present form in its comparatively 

 long centrum. 



47420. A large left coracoid, probably belonging to this or the 

 preceding species ; from the Upper Lias of the Yale of 

 Bel voir, Leicestershire. Allowing for the absence of the pos- 

 terior extremity, this specimen closely resembles No. 32669. 

 Its transverse diameter is 0,220. Purchased, 1876. 



b. Tenuirostrine Subgroup. 



Teeth and mandible of same general structure as in preceding 

 subgroup. Vertebrae apparently similar to those of the typical 

 subgroup of the Latipinnate group. Coracoid with posterior notch. 

 Humerus with the proximal extremity triangular, and the longer 

 axis of the same directed transversely ; the structure of this bone 

 thus corresponding with that of the femur. Pectoral limb larger 

 than pelvic. The pubis and ischium are short and wide. 



In the structure of the limbs this and the next subgroup appear 

 to be the most generalized forms of the genus : this being especially 

 shown in the similarity of the humerus to the femur. The rela- 

 tively small size of the pelvic to the pectoral limb indicates, however, 

 that this group is more specialized than /. platyodon ; since it is 

 most probable that the order was derived from Eeptiles in which 

 the pelvic limb was at least as large as the pectoral. 



The structure of the coracoid indicates affinity with 7". communis. 



