49S APPENDIX. 



DESCRIPTIONS 



OF SOME NEW AUSTRALIAN REPTILES. 



By John Edward Gray, Esa., F.R.S., &c. 



Fam. Saukid.e. 

 SiLUBOSAURUs, Gray. 



Head subquadrangular, raised in front, head-shields flat, thin, 

 rather rugose. Nasal shields ovate, triangular, rather anterior, with 

 a groove behind the nostril. Rostral shields triangular, erect. 

 Supranasal none ; internasal broad ; frontonasal large, con- 

 tiguous ; frontal and interparietal small, frontoparietal and pa- 

 rietal moderate; eyebrow shields, 4-4. Temples scaly, no 

 shields between the orbit and labial plates. Eyes rather 

 small, lower lid opatic, covered with scales. Ears oblong, with a 

 large scale in front. Body fusiform, roundish thick; scales of the 

 back, broad, lozenge-shaped, keeled ; keels ending in a dagger 

 point ; largest on the hinder parts of the throat and belly ; trans- 

 verse, ovate, 6-sided. Limbs four, strong. Toes elongate, com- 

 pressed, unequal, clawed ; tail short, conical, tapering, depressed ; 

 with rings of large, broad, lozenge-shaped, dagger-pointed, spinose 

 scales, with a central series of very broad 6-sided smooth scales 

 beneath. 



This genus is intermediate between Cydodus and Egernia, but 

 quite distinct from both. It differs from Tachydosaurus and Cy- 

 dodus in ha-^-ing slender elongated toes like Egernia, in the scales 

 being keeled, and in there being no series of large plates beneath 

 the orbit, and it is easily known from Egernia by the tail being 

 depressed and broad, instead of conical and round. Like all the 

 genera above named, it appears to be peculiar to Australia. 



