BATRACIIIANS AND REPTILES, CENTRAL AMERICA AND MEXICO. 40 



ton, besides a considerable number in my own collection. I'or the characters of 

 many genera Avhich I have not seen I have had to rely on the descriptions of othcrsj 

 especially of Drs. Peters and Giinther. 



EPANODONTA, 



Typhlopidje. 



I. Muzzle covered above by rostral and iuternasal scuta. 



a. Two ocular plates and a proocular. 

 One nasal plate Lethcohia Cope. 



cxcx. One ocular and a preocular. 



One nasal plate Tijphlop^ Schn. 



Two nasal plates lIclminthopMs^ Pet. 



aaa. One ocular and no preocular. 



One nasal plate Ti/phliiia- Wagl. 



Two uasal plates Liottjphluini-^ Pet. 



II. Muzzle aud front with iivo Rymmetrical scuta. 



Two nasals and a preocular Anomaltpis Jan. 



CATODONTA. 



SlENOSTOMIDiE. 



Superciliarj- scales present SUnostoma Wagl. 



No superciliary scales Ilena B. & G,* 



TORTRICINA. 



ToRTRICir)^. 



Intermaxillary bone dentate ; eye covered by a single scute Torfrix Oppel. 



Intermaxillary edentulous; eye surrounded by distinct scales CtjlindropMs Wagl. 



Ukopeltid.e. 



I. Tail terminating in a large shield. 



Rostral plate produced posteriorly, separating the nasals Ehinophis Hemp. 



Rostral not produced ; nasals in contact Uropelth Cuv. 



II. Tail scaly to end. 



Tail terminating in a disk of keeled scales; supraorbitals and postocular confluent. 



Sili/bura Gr. 

 Tail compressed, truncated, terminating iu a bicuspid scale, the points superposed; 



postocular distinct rivctrurus D. & B. 



Tail tapering, terminal scute ending in a hocizontal ridge; no chin-groove. 



Platyplcctruriis GUnth. 



Tail tapering, ending in a single point; no chin-groove Teretrurus Bedd. 



Tail with smooth scales, terminating in one or two points; postocular united with 

 superciliary; a median chin-groove Melanopliidium Gthr. 



ASINEA. 

 Xenopeltid.e. 



Eyes not covered with a plate ; head with normal shields, with an interparietal 

 added ; scales smooth ; anal and subcaudals divided ; teeth 

 equal XenopeUis Remw. 



^ Idiotyphlops Jan. 



Tilidinn Duni. Eibr. Typhlinaliii Gray. 



^lihinotypldops I'et. 



^CatodonD. & IJ., not of Laceii. Siarjonodon Peters. 



