CROCODILIANS, LIZARDS, AND SNAKES. 673 



ward, so as to inclose partially the posterior uares below. The pala- 

 tines are short, the groove separating the maxillary from the vomerine 

 l^rocesses extending to the suture with the pterygoid, so that the max- 

 illary process only appears as the inferior face of the bone. Ptery- 

 goids elongated anteriorly, reaching to beyond the middle of the 

 palatine foramen. They extend directly back to the quadrates, being 

 well separated on the middle line, and abruptly notched on the inner 

 side to receive the short, angular basipterygoids. They are separated 

 from the sphenoids by a fissure, and are grooved on the inner side pos- 

 terior to the basipterygoid. Ectopterygoids present, rather slender, 

 inclosing rather large palatine foramina. Ej^ipterygoid small. Narial 

 fissure overhung by the free edge of the maxillary and palatine bones. 

 Sphenoid and basioccipital and exoccipital coossified. Occipital con- 

 dyle convex and perfectly simple. 



The mandible has an open Meckelian groove, and the surangular and 

 articular bones are coossified, while the angular and spleuial bones are 

 distinct. The latter extends well anteriorly. The coronoid extends a 

 little forward on the exterior face of the ramus and in both directions 

 on the inner face. 



The hyoid apparatus is the most simple among lizards. It consists 

 of a continuous cartilaginous glossobasihyal rod, which is bifurcated 

 posteriorly, and a simple osseous first branchihyal attached to each of 

 the branches. Other elements wanting. 



Ten cervical vertebra' with compressed inferior processes of the cen- 

 tra, or hypapophyses. They are coossified with the centra and are not 

 intercentral in position, hence it is not evident that they are inter- 

 centra. No zygosi)hen. In the AnnicUa pulehra there are seventy- 

 three rib-bearing vertebra' and two cervicals without ribs. The sacral 

 and proximal caudal vertebne have diapophyses, those of the former 

 little different from those of the latter. The fifth vertebra with a 

 diapophysis supports a pair of parallel plates coossified with its infe- 

 rior face like the chevron or double hypapophysis of a snake. In the 

 succeeding vertebrae similar plates form the basis of a chevron, whose 

 symphysis is turned rather abruptly posteriorly. The position of 

 these chevrons is central and not intercentral. Caudal vertebne not 

 segmented. 



Scapular arch wanting; pelvic arch medi ventral; no limbs. The 

 ilium is represented by a small and short rod like bone, which is attached 

 to the extremity of the diapophysis of a single vertebra. The proximal 

 extremity is directed backward for a short distance posterior to the 

 point of suspension, as in Aneli/tropsis. According to Baur, there is a 

 rudimentary ischium and pubis, "which are united proximally." jSTo 

 trace of posterior limb. Teeth simple, acutely conic. 



The hemipenis is not bifurcate. It is surrounded by transverse 

 laminae or flounces, which are crimped so as to be slightly pocketed. 

 The organ resembles that of Gerrhonotus. 

 NAT MUS 98 43 



