124 MEMOIRS OF THE CARNEGIE MUSEUM 
to Professor Seeley’s incorrect determination of the borders of the coracoid, as has 
already been indicated by Lydekker,” “the one marked intercoracoidal being really 
the glenoid cavity.” This correction is substantiated by the material under consid- 
eration in this paper, and the clavicles instead of enclosing the coracoids (made im- 
possible by the articulation between coracoid and scapula), curved up in front of the 
scapulee as in Ichthyosawrus. 
In 1888 in the “Catalogue of Fossil Reptilia and Amphibia in the British Mu- 
seum,” Lydekker gave the following characterization of the genus : 
“Teeth present but apparently small, and perhaps confined to the anterior por- 
tions of the jaws. Humerus and femur with strongly developed trochanteric ridge 
on dorsal surface, and articulating distally with three bones, as in Baptanodon, which 
are of irregular polygonal contour. ‘The ulna being pentagonal. Clavicles (typically) 
separate, with the interclavicle wedged in between them. Vertebral centra of the 
general type of those of Campyldont subgroup of Ichthyosawrus. Coracoid without 
posterior notch. Humerus and femur apparently (except at distal end) of the gen- 
eral type of those of I. campylodon and relatively large in proportion to the vertebre. 
In Baptanodon and probably also in this genus both pectoral and pelvic limbs rela- 
tively wide (or that arising from the intermedium) contains two such rows, with the 
consequent presence of two centralia.” 
In 1898 Woodward® confined most of the observations made by Seeley and 
Lydekker, and added important information concerning the pelvic region, 7. e., 
“The pubis and ischium are fused together, leaving a small obturator foramen.” 
Besides, he figures a right pectoral limb which shows that member as being com- 
posed of the normal number of five digits. 
Combining the characters given by the different authorities the genus Ophthal- 
mosaurus may be distinguished by the following : 
Gen. char.: Teeth present but apparently small and perhaps confined to the anterior 
portions of the jaws. Clavicles (typically) separate with the interclavicle wedged in between 
them. Coracoids without posterior notch. Humerus and femur with strongly developed 
trochanteric ridge on dorsal surface and articulating distally with three bones, which are 
of irregular polygonal contour. Ulnais pentagonal. Pubis and ischiwm fused together, 
leaving a small obturator foramen, 
Two species of this genus have been described of which a brief review is given 
The type specimens are from the Jurassic and Lower Cretaceous of England. 
5 Lydekker, R., ‘‘ Cat. of Fossil Reptilia and Amphibia in the British Museum.’’ Part II. 
5 Woodward, A. S., “‘ Vertebrate Paleontology,’’ p. 183. 
