BATRACHIANS AND REPTILES, CENTRAL AMERICA AND MEXICO. 53 



Two nasals in contiict w itli frcnoocular Lcptocalamus Gtlir. 



aa. Teeth e(iual. 

 0. Superciliary i^late absent. 



Two nasals and a freuoorbital Colophrys Cope. 



/?/?. Superciliary present. 

 y. Rostral plate produced. 

 S. Nasal plates distinct. 



Noloreal; anal divided; two nasals Geaoran^ Cope. 



A loreal ; anal entire ; two nasals Cemophora Cope. 



A loreal; anal divided; ono nasal Chionactis'^ Cope, 



Sd. Nasal plates united witli internasals. 



A preocular and a divided anal Chilomeniscns'^ Cope. 



yy. Rostral i>late not produced. 

 £. Palatine bones with teeth. 

 ?/. One nasal plate ; one anal plate. 



Scales smooth , IIomalosoma*'Wsig\. 



Tfi]. One nasal and two anal plates. 



Loreal and preocular present Coniia^ B. «fe G. 



Loreal present, no preocular Ahastor'' Gray. 



Neither loreal nor preocular Oxyorrhos^ Fischer. 



ippj. Two nasal, one anal plate. 

 Maxillary bone very slender ; scales smooth ; a frenoorbital plate, 



Stenognailms.^ D. & B. 



Maxillary more robust ; scales smooth ;"a frenoorbital iilate Bhabdosoma'^ D. «&- B. 



Maxillary more robust ; scales keeled : a frenoorbital plate Elaj)oidea^^' Boie. 



r/T/rpf. Two nasal and two anal scuta. 



AJoreal; no jireocular ; two pairs geneials FirgiiiiaB. & G. 



A loreal; no preocular; one pair geneials Adelphicus^^ Jan. 



A loreal and a preocular ; two pairs geneials Snnora B. & G. 



Noloreal; a preocnlaf ; jaws weak lirachyorrhos Kuhn 



££. Palatine bones without teeth. 



Two anals and nasals ; a loreal and a preocular OJujodon Boie. 



Two anals and nasals ; a loreal and no preocular Colohognatlais Pet. 



ft Nasal scutum mimite. 



No internasals ; preoculars present CaJamaria Boie. 



Two internasals ; a preocular Fseudorhahdium Jan. 



Two internasals; no preocular Oxycalamus Cant. 



ttt No nasal scutum. 

 No loreal, nor pre- nor postocvdar Typhlogeopliis Giinth. 



COROXELLIN^. 

 T. No palatine teeth. 



Anals two; one internasal ; scales smooth TnpeZ/is'- Cope. 



Anal plate divided ; two internasals ; scales smooth Oligodon^^ Boie. 



' Enulius Boc. Sphenocalamus Fiscli. Pnendofiscimia Boc. 



'' Lamprosoma Hallow. 



3 Bergenia Steindacliner. 



^ Rhabdium D. & B. 



'^ Cryptodacus Petera. FArenis Jau. 



^ Oarphophiops Gerv. Carphophis D. & B. CeliUa I!. &. G. 



'1879; Atractoceph(dus^Vi\\\. ? 1880. 



** Flatypteryx D. & B. 



"> Rhabdium D. & B. 



i(i6'eoj)/i('s AVagl. Catastnma \Vn<i,]. 



" Jihabdosoma Boo. iiotT). & B. Jiher!)wps Coiic 



"Gini. nov. tyj)*^ Olijodun ]irenicaud<t Glliv. 



"/ Rhynchocalamus Gtlir. 



