27. TROPIDTJEtJS. 171 



27. TROPIDURUS. 



Tropidunis, Wied, Abhild. Kat. Bras.; Fitzing. Syst. Eept. p. 71 ; 



Peters, Mon. Berl. Ac. 1871, p. 044. 

 Tropidurus, part., Fitzing. N. Classif. Rept. p. 17 ; Wagler, Syst. 



Amph. p. 14G ; Wiegm. llerp. Mex. p. 18. 

 Ecphvmotes {non Fitz.), Cuv. JR. A. 2ud ed. ii. p. 47 ; Dtwi. S,- Bihr. 



iv.'p. 342. 

 Platjnotus, Wagler, I. c. 

 Microlophus, Bum. 4'" Bihr. p. 3-34 ; Gray, Cat. Liz. p. 221 ; Peters, 



I.e. 

 ? Tropidogaster, Dam. S^- Bihr. p. 329 ; Gray, I. c. p. 227. 

 Steirolepis, Fitzing. I. c. p. 72. 

 ? Tritropis, Fitzing. I. c. p. 59. 

 Taraguira, Gray, I. c. p. 219. 

 Eulophus, Tschudi, Faun. Per., Herp. p. 25, 

 Craniopeltis, Peters, I. c. p. 645. 

 Lfemopristus, Peters, I. c. 

 Aueuporus, Bocourt, Miss. Sc. Mex., Rept. p. 215. 



Tympanum distinct. Body more or less compressed or depressed, 

 without or with a more or less developed dorsal crest. Dorsal scales 

 uniform. Upper head-scales enlarged, occipital very large. A 

 strong curved or oblique fold on each side in front of the shoulder, 

 not extending across the throat ; frequently a transverse fold in 

 front of the latter ; no gular sac. Digits compressed, with keeled 

 lamellae inferiorly. No femoral or pra^anal pores. Tail long, sub- 

 cylindrical or compressed. Lateral teeth tricuspid ; pterygoid teeth. 

 A sternal fontanelle. No abdominal ribs. 



South America. 



Synopsis of the Species. 

 I. Nostril above the canthus rostralis ; ventral scales smooth. 

 A. A dorsal denticulation or crest, distinct at least on the nape. 



1. Dorsal scales larger than ventrals. 



a. A strong oblique antehumeral fold, not meeting its fellow 

 on the breast ; no transverse gular fold. 



Dorsal scales more than twice as large 



as ventrals 1. grayi, p. 172. 



Dorsal scales little larger than ventrals . . 2. pacijicus, p. 173. 



h. A transverse gular fold in front of the oblique ante- 

 humeral fold. 



Scales on the snout keeled 3. occipitalis, p. 173. 



Scales on the snout smooth 4. bocourtii, p. 173. 



2. Dorsal scales not larger than ventrals. 



Dorsal scales smaller than ventrals ; sides 



of neck uniformly granular 5, peruvianus, p. 174. 



