206 TGtTANID.E. 



Megadactvlus, Fitzing. Sijst. Rept. p. 59. 

 Homalosaurus, Hallow. Proc. Ac. Philud. 1852, p. 179, 



Tympanum distinct. Body depressed ; no dorsal crest ; dorsal 

 scales small, uniform. Upper head-scales small, occipital very 

 large. Two transverse gular folds, the posterior with denticulated 

 border ; no gular pouch. Digits with sharply keeled lamellae 

 iuferiorly. A long series of femoral pores. Tail rather short, de- 

 pressed. Lateral teeth indistinctly tricuspid ; no pterygoid teeth. 

 A large sternal fontanelle. Xo abdominal ribs. 



South-western Xorth America. 



1. Callisaurus draconoides. 



Callisaurus draconoides, Graii, Cat. p. 227. 

 Callisaurus draconoides, Blainv. I.e. p. 286, pi. xxiv. fig. 2; Dum. Sf 



Bibr. p. 326 ; Bocourt, I. c. p. 158, pi. xvii. bis. fig. 10. 

 Megadactylus draconoides, Fitzing. I. c. p. 60. 

 Homalosaurus ventralis, lialloiv. I. c. p. 179, and in Sitgreavc's Exped. 



Zuni S)' Color. Biv. p. 117, pi. vi. 

 Callisaurus ventralis, Baird, U.S. Mex, Bound. Surv., Bept. p. 8. 



Head small, much depressed, upper lip projecting ; nostril large, 

 superior ; ear-opening large, vertically oval. Head-scales small, 

 irregular and smooth, largest on the snout ; occipital large, a little 

 broader than long ; a large infraorbital scale ; upper labials rather 

 large and oblique. Dorsal scales uniform small juxtaposed granules; 

 ventral scales larger, flat, squarish or subhesagonal, smooth. A 

 slight fold along each side. Limbs very long ; the adpressed hind 

 limb reaches the tip of the snoiit, or beyond ; digits long. Sixteen 

 or seventeen femoral pores on each side. Male with enlarged post- 

 anal scales. Tail long and slender, depressed, covered, with small 

 smooth scales. Greyish above, dotted with white ; tail and limbs 

 with angular dark cross bands ; a white and blackish streak along 

 the hind side of the thighs ; lower surfaces white ; a bluish band 

 (males) on each side of the belly, crossed by two [or three] oblique 

 black spots ; lower surface of tail with transverse black spots. 



millim. millira. 



Total length (tail reproduced) 155 Body 76 



Head 18 Fore limb . 45 



Width of head 13 Hind limb . . 77 



California to Texas. 



a-h. (S . ? Smithsonian Institution [P.], 



46. UMA. 



Uma, Baird, Proc. Ac. Fhilad. 185S, p. 253 ; Cope, eod. loc. 1860, 

 p. 310. 



"Ears distinct. A very long infraorbital plate. Palate without 

 teeth. Outer face of upper labials plane and broadly vertical ; the 

 labials themselves much imbricated, and very oblique. Scales of 



