58 BULLETIN 32, UNITED STATES NATIONAL MUSEUM. 



LYCODONTIN^. 



I. Autorior tnaxillaries not isolated. 



a. Subcaudal scuta double. 

 fi. Dorsal scales of equal size. 

 Two nasals; nosti'il in tlieauterior; aloreal; body much compressed.. Zf/corfrj/as Gthr. 



Two nasals; nostril between; body not compressed; lores plaue BoUdon^ D. & B. 



Two nasals; body not compressed ; lores longitudinally grooved. 



Bothroplithalmus"- Schl. 



Two nasals; nostril in the anterior Lycophidium^ Fitz. 



One nasal ; a loreal Meioporhina Gthr. 



f^j3. Dorsal scales of unequal size. 



Vertebral series sniooth ; body compressed Hormonotus Hallow. 



Vertebral series suiooth; bocjy round Lamprophis Fitz. 



Vertebral series bicarinate ; body round Simocepkalun* Gray 



aa. Subcaudal scutella eutiro. 

 Two nasals ; scales equal, smooth HolurophoUs Dum. 



II. Anterior maxillaries isolated. 



a. Subcaudals in two rows. 

 (3. Nareal region with a pit. 



Scales smooth; anal entire Bolhroh/cus Gthr. 



/?. No nareal pit. 

 y. Longest teeth at middle and posterior end of maxillary bone. 



Two nasals ; body round Dinodon^' D. & B. 



yy. Longest teeth at front of maxillary. 



Scales keeled ; two nasals ; a loreal Ophites Wagl. 



Scales suiooth ; two nasals; a loieal Lycndon Boie. 



Scales smooth ; two nasals ; no loreal . . .' Tetra(ioiwsoma Gthr. 



Scales smooth ; one nasal; aloreal Leptorhylaon Gthr. 



aa. Subcaudal plates in one row. 



Scales keeled C'Crcanpin Wagl. 



Scales smooth Cydocorus D. & B. 



LEPTOGNATHINyE. 



a. Subcaudal scuta entire. 



Teeth of equal length • A iioplodiijsas Pet. 



Teeth elongate posteriorly Dipmidoboa Gthr. 



Teeth longer anteriorly Amhlycephalus Kuhl. 



aa. Subcaudal scuta in two rows. 

 j8. A median geneial plate. 



Maxillary bone very short; one nasal plate Asthoiodipsaa Pet. 



Maxillary bone long; two nasal plates Mesopdtis'' Cope. 



/3/?. No median geneial plate. 



Teeth equal ; no internasals ; two nasals Diptltophin Cope. 



Teeth weak; equal; internasals; two nasals Lcptoynatltus D. »& B. 



Teeth longer in front ; internasals ; one nasal I'areas Wagl. 



DIPSADIN.E. 



I. Subcaudal scuta. 



Parietal plates rei)laced by scales ; other plates normal Pythonodipsas Gthr. 



II. Subcaudal scutella. 



a. No teeth anterior to the grooved maxillary. 

 Scales smooth Opisihoplus Pet. 



aa. Median maxillary teeth not much shortened. 

 Nostril large, between two nasals and the internasal; vertebral scales larger, 



Ehinobolhryum Wagl. 



^ EugnaUntsi I). & Ji. * JJeterolepis iin\. Diaphorolopis Jan. 



^Belongs pfiluipM to Cohiltrin.i). '' Mumesodon Uope. 



^Alopecium D. &.R. ^ Antliertoi/nathuii Hoc. 



