Cope.] l^O [March 18, 



anterior to semicircular canal; the anterior border continued into a crest 

 which runs posteriorly above the trigeminal foramen. This terminates at 

 the down looking crest of the subforaminal portion, wliich bounds exter- 

 nally a wide down-looking groove. Basipterygoid processes long. Sphe- 

 noid distinct from basioccipital. Occipital condyle subequally divided 

 into three parts, two prominent exoccipilals and a contracted basioccipital. 

 The result is an apparently double condyle. 



Mandible with the Meckelian groove closed, and with the splenial 

 small and but little produced beyond the splenial foramen. Corouoid 

 produced a little horizontally at the base. Angular not distinct; suran- 

 gular and articular distinct. Angle simple, direct, spoon -shaped, witli 

 superior concavity. I have observed the following peculiarities in the otic 

 and hyoid regions. There is no infrastapedial cartilage, and the supra- 

 stapedial and epistapedial cartilages are continuous. The hyoid system 

 is characterized by the fact that the ceratohyal is attached to the paroc- 

 cipital, which carries a cartilage on its extremity. There is a short second 

 ceratobranchial, and no free epibrauchial. 



Vertebrae amphicojlous. lutercentra present throughout the vertebral 

 column, continued into chevrons on the caudal region. Cervical ribs 

 widened and truncate at extremities. In the specimen described the diapo- 

 physes of the second sacral vertebra are deeply longitudinally grooved on 

 the inferior side so as to be nearly split. Diapophyses of anterior caudals 

 elongate. Neural spines distinct but low throughout the column. In the 

 scapular arch 1 note the following peculiarities. There is no proscapula, 

 and the clavicle is much enlarged, and is perforate at the median extremity. 

 The interclavicle is cruciform with the angles filled up so as to have con- 

 cave borders. It is coossifled vvith the clavicle in P. tuber culatus, and ex- 

 tends but a little way posteriorly on the sternum. The coracoid has one 

 large foramen. The sternum has no fontanelle. There are four htiema- 

 pophyses attached to the sternum on each side ; and two to each of the 

 slender closely approximated xiphoid rods. There are several very slender 

 abdominal ribs. 



The ilium has no angulus cristce, and the acetabulum is entire. The 

 pubes join at a little less than a right angle, and the pectineal processes 

 are short and a little posterior to the middle. Pubes uniting at less than 

 a right angle below, with the 'tuberosities distal. 



The most distinctive feature of the skeleton of this genus is the pres- 

 ence of intercentra throughout the vertebral column, a point in which it 

 resembles the extinct Theromora of the Permian epoch. 



EuBLEPHARis Gray. * 



Owing to the isolated position of this genus its osteology is worthy of 

 especial attention. The premaxillary is undivided, and has a long supe- 

 rior spine but no inferior spine. The nasals are distinct. The frontals 



* I include in this genus the Coleonyx of Gray, which does not differ generically from 

 the other American species of the family. 



