84- Edwin Chapin Starks. 



cavity, or coterminous with the temporal crests. From the front of 

 the supraoccipital a broad low rounded ridge runs obliquely across 

 the frontal outward and forward toward the middle of the orbital 

 cavity where it becomes lower and broader and merges into the gen- 

 eral level of the frontal. Against this ridge the pterotic and tem- 

 poral crests end a short distance from the orbital rim. A thin high, 

 auxiliary crest is developed between the anterior ends of the tem- 

 poral and pterotic crests. The myodome is large, but posteriorly its 

 opening is closed all l)ut a small transverse slit by the parasphenoid. 

 The supraoccipital widely separates the parietals and is developed 

 a little anterior to them. Posteriorly it covers the suture between 

 the extreme upper ends of the exoccipitals, but it nowhere separates 

 them. The exoccipitals do not meet over the basioccipital at the 

 mouth of the long tunnel-like foramen magnum, though some distance 

 in the foramen they are in contact for a short distance. The verte- 

 bral condyles of the exoccipitals are very small. They are anterior 

 to the basioccipital condyle instead of overhanging it as usual, and 

 they slope outward and forward away from the median line, rather 

 than outward and backward or toward the median line. The pterotic 

 ends posteriorly in a sharp spine and there is no deep pit between it 

 and the prootic and sphenotic. There is no pit on the lower part of 

 the cranium behind the prootic, and the pterotic is not excluded from 

 the brain cavity. The opisthotic is as in the majority of spiny-rayed 

 fishes: covering the suture between the pterotic and exoccipital, but 

 not at all separating them. It is wholly on the ventral surface of 

 the skull, and the lower limb of the posttemporal is attached to its 

 posterior edge. The lateral process of the parasphenoid does not 

 reach to the upper edge of the prootic. The vomer is broad and 

 thick and on. its outer anterior edge is an oblique facet, which fits 

 snugly against the inner surface of the maxillary. The vomer and 

 palatine bear small teeth. 



The prefrontals broadly meet at the median line behind the eth- 

 moid ; they are pierced by the olfactory foramina. There is an articu- 

 lar facet on the posterior end of each, and another on the anterior end 

 of the ethmoid for the attachment of the palatine. The ethmoid is 

 but little posterior to the front of the vomer, and it is broadly rounded 



