176 iGUANri)^. 



small pouch on each side of the throat. Sides of neck irregularly- 

 folded, with groups of small spinose scales. A small dorsal crest, 

 most developed on the nape. Dorsal scales small, rhomboidal, im- 

 bricate, keeled, ending in a spine, obliquely directed towards the 

 vertebral line ; lateral and ventral scales as large as dorsals, latter 

 smooth. The adpressed hind limb reaches the shoulder, or between 

 the latter and the ear. Tail roundish, with serrated upper ridge ; 

 caudal scales larger than dorsals. Upper surfaces olive, lighter- 

 dotted, with ill-defined dark brown crescentic cross bands ; sides 

 bluish ; antehumeral fold black ; lower surfaces yellowish, throat 

 clouded with blackish. 



millim. millim. 



Total length 284 Fore limb 59 



Head 28 Hind limb 80 



Width of head 25 Tail (reproduced) . . 150 



Body 106 



Paraguay ; Argentine Eepublic. 



a-b. S • Paraguay. 



c,d. d'. Cosqiun, Cordova. E. W. White, Esq. [C.]. (Types of 



Leiocephalus variegatus.) 



7. Tropidunis torquatus. 



Taraguira torquata, Gray, Cat. p. 220. 



darwinii, Gray, I. c. 



Stellio torquatus, Wied, Reise n. Bras. i. p. 139. 



Tropidurus torquatus, Wied, Beitr. Nat. Bras. i. p, 137, and Abbild. ; 



Reinh. Sf Liitk. Vidensk. Meddel. 1861, p. 227 ; Peters, Mon. Berl. 



Ac. 1877, p. 409. 

 Agama tuberculata, Spix, Spec. Nov. Lacert. Bras. p. 12, pi. xv. fig. 1. 

 Ecphymotes tuberculata, Guer. Icon. R. A., Rejit. pi. xii. fig. 2. 



torquatus, Dum. S)- Bibr. iv. p. 344. 



Tropidurus microlepidotus, Fitziny. Syst. Rept. p. 72. 

 Taraguira torquata, Girard, U.S. Kvplor. £xj)ed., Iferp. p. 318. 



Upper head-scales smooth ; a series of transversely enlarged supra- 

 oculars, the width of which never exceeds half the width of the 

 supraocular region ; occipital usually longer than broad, and nar- 

 rower than the supraocular region ; temporal scales flat and feebly 

 keeled ; a fringe of long scales in front of the ear. A strong, 

 slightly curved antehumeral fold, widely separated from its fellow ; 

 one or two more or less marked transverse gular folds ; sides of neck 

 granular, with one or two oblique folds or pouches. 'No dorso- 

 nuchal ridge. Dorsal scales small, slightly larger than ventrals, 

 keeled, rhomboidal, imbricate, and ending in a short spine in the 

 males, subhexagonal in the females and young ; keels of the dorsal 

 scales forming obli(iue lines ; ventrals smooth. The adpressed hind 

 limb reaches the ear or the eye. Tail once and one fourth to once 

 and a half as long as head and body, round or slightly compressed ; 

 caudal scales much larger than dorsals, ending in a spine. Olive or 

 brownish above, usually with darker spots and lighter dots ; usually 

 a more or less distinct light and a dark lateral dorsal band ; a black 



