800 SCIENTIFIC RECORD FOR 1885, 



clavicles dilated and loop-shaped proximally, and no post-orbital or 

 post-fronto squamosal arches. 



{Pygopodidce.) — The only known Pygopodoidea, especially marked by 

 the exclusion of the frontal from the orbit, by the retention of the pre 

 and post-frontal bones towards each other so that they are in con- 

 tact. 



Agamoidea. — Eriglossate saurians with concavo-convex vertebrae, 

 clavicles not dilated proximally, and without post-orbital or post-frontal 

 squamosal arches. 



(Agamidce.) — Agamoidea with the supra-temporal fossa not roofed 

 over by bone, tongue thickened, and aerodont dentition. 



{Iguanidce.) — Agamoidea with the supra temporal fossa not roofed 

 over by bone, tongue thickened, and a pleurodont dentition. 



[Xcnosauridw.) — Agamoidea with the supra-temporal fossa not roofed 

 over by bone, the interior portion of the tongue retractile, a i)leurodont 

 dentition, and T-shaped inter-clavicles. 



{Zonuridce.) — Agamoidea with the supra-temporal fossa roofed over, 

 the tongue simple, and cross-shaped inter-clavicles. 



(Anguidce.) — Agamoidea with the supra-temporal fossa roofed over; 

 tongue with its anterior portion retractile, with clavicles cross-shaped 

 or absent, and the exo-skeleton developed as osteo-dermal plates, 

 each provided with a systeni of irregularly arranged aborescent or rad- 

 iating tubules. 



Anielloidea. — Eriglossate saurians, with concavo convex vertebrae, 

 clavicles not dilated posteriorly, and without post-frontal squamosal 

 or post-orbital arches. 



[Aniellidce.) — The only known anielloidea, distinguished by the ab- 

 sence of ante-orbital septum, and of the columella cranii, and without 

 squamosals. 



Helodermatoidea. — Eriglossate saurians with concavo-convex verte- 

 brfe; clavicles undilated proximally, and post orbital bony arches, but 

 without post-fronto squamosal arches. 



{Helodermaiidw.) — The only known family of the super-family, distin- 

 guished further by the exclusion of the frontal from the orbit on account 

 of the convergence and contact of the pre and post-frontals. 



Varanoidea. — Eriglossate saurians, with concavo-convex vertebrae; 

 clavicles not delated proximally ; post-orbital arches, rudimentary or 

 absent, and with post-fronto squamosal arches developed. 



( Varanidce.) — The only known forms of the type, distinguished further 

 by the union of the nasals into a single bone and the ensheathment of 

 the tongue at its base and its deeply bifid emargination anteriorly. 



' Lacertoidea.— Eriglossate saurians with the vertebrae concavo-convex ; 

 clavicles undilated proximally, and post-fronto squamosal at post-orbi- 

 tal arches developed. 



{Xantusiidce.) — Lacertoidea with the supra-temporal fossa roofed over 

 and the parietals distinct. 



