1S92.I 1*^^ [Cope. 



are well developed. Tiie latter are only separated from each other l)y 

 liiranieut or cartilage, which may sometimes contain some lime salt. It 

 is produced posterior to the ischia in a triangular process, and less fre- 

 quently into a similar one in front of the pubic symphysis. The pubic 

 foramen is always present. The pectineal process is present except in 

 Gecconidie, but it is rudimental in some forms, as Phrynosoma. The fol- 

 lowing table shows the forms of the pubis in twenty-three genera of dif- 

 ferent families : 



I. Pubes uniting at an acute angle. 



1. Pectineal process anterior Chamadeon. 



3. Pectineal process median Calotes, Draco, 



Iguana Dipsosaurus Anolis, 

 Oerrhonotus, 



Tupinam his CnemidopJiorus. 



3. Pectineal process near acetabulum Scincus, 



Lacerta, 

 Eumeces (rudimental). 



4. No pectineal process. Oonyocephalus. 



II. Pubes uniting at an obtuse or very open angle. 



1. Pectineal process median Iguana Cyclura Crotaphytus, 



Histiurus, 



3. Pectineal process near acetabulum Agama, 



Ihrynosoma Sauromalus Sceloporus, 



Heloderma, 



Varanus. 



3. Pectineal process none Gecko {Phrynosoma, rudiment). 



There is a tuber ischii in all of the genera which have come under my 

 observation except Varanus. In Heloderma and some other forms it is 

 small. 



5. The Anterior Limb. — The humerus is much alike in all Lacertilia, 

 Chamseleo only presenting peculiarities. The proximal end is expanded 

 nearly in one plane, and the middle portion of the flattened extremity 

 forms the oval head. This is not distinctly isolated, except by the pres- 

 ence of articular surface, from the greater and lesser tuberosities which 

 occupy the angles of the expansion. The shaft betrays no twist. The 

 distal end is chiefly occupied by the condyles ; but there are epicondyles, 

 of which the internal is the more prominent, except in Chamatleon, where 

 they are wanting. The condyles consist of an external rib and a medio- 

 internal roller, which is generally bounded at the internal extremity by a 

 tuberosity, which is, however, wanting in Chamseleon. The ulna artic- 

 ulates with the median roller, its external edge being beveled by the ex- 

 ternal rib. The head of the radius articulates with the external rib, hav- 

 ing shifted from its primitive position on the inner side. It results from 

 this that in pronation the radius crosses the ulna. There is a short ole- 



