1884.J ■^* • [Cope. 



nation, which I give above. It is allied to Dimades, Abastor, etc., but 

 differs from tliem all in having a grooved posterior maxillarj- tooth. The 

 characters of the genus Ilydrocalamus are : 



Opisthoglyph. Two internasal and two prefrontal plates. Two nasals, 

 a loreal, and one preocular. Anal scutum divided. Scales smooth. 



The genus difiers from the nearest opisthoglyph calamarians as follows : 

 From Elapomorphus and Scolecophis in ihe divided anal scutum, and 

 from the former in its two nasals : from Procinura in the absence of the 

 rugosities of the caudal scales. 



LiMNOPHis SEPTEMViTTATUS. Calopismcc sejJtemvMata Fischer, Verhandl. 

 Xaturwiss. Verein, Hamburg, 1879, p. 84, PI. i, f. 3. 

 This species agrees exactly with Limnophis Giinther in scutellation, 

 and approaches very nearly in dentition. It is not referable to any other 

 genus now named. 



Trimetopon gracile. Ablahes gracilis Giinther. Ann. Magaz. Xat. 

 Hist., 1872, p. 18. From Costa Rica, Giinther. 

 The characters of the genus Trimetopon are as follows: 

 Two iKternasals ; one prefrontal plate. Two nasals ; rostral not pro- 

 duced ; a loreal and one preocular. Scales smooth, with one pore. Anal 

 divided. 



There are three other aglyphodont calamariform genera, with one pre- 

 frontal piate. From Colorhogia Cope, Trimetopon differs in having two 

 nasal plates; from Opisthotropis Giinth., in having smooth scales; and 

 from Chersodromus R. & L., in the presence of a preocular plate, and in 

 the smooth scales. 



Gyalopium PtJBLiUM Cope. American Naturalist, 1884, p. 163. Ficimia 

 publia Cope, Proceeds. Acad. Phila., 1866, p. 126. Ficimia ornata 

 Bocourt, Miss. Sci. Mexique, 571, PI. xxv, f. 10. 

 Hab. Yucatan, Schott. 

 Geagras redixiitus Cope. Journal Acad. Philada., 1875, p. 141. 

 Sphenocalamus Uneolatus Fischer, Oster Programm des Akad. Gym- 

 nas., Hamburg, 1883, p. 5, PI. i, figs. 3-5. 

 Tehuantepec, Sumichrast ; Mazatlan, Fischer. 

 Geagras frontalis Cope. Journal Academy Philada., 1875, p. 142. 

 Toluca frontalis Cope. Proceeds. Acad. Phila., 1864. p. 147. Pseudo- 

 ficimia pulchra Bocourt. Miss. Sci. Mexique, 572, PI. xxxv, f. 12. 

 Colima, Xantus ; Guadalaxara, Major. 

 Geagras sumichrasti Bocourt. Cope, Amer. Naturalist, 1884, p. 162. 

 Eiudias sumichrasti Bocourt. Miss. Sci. Mexique, 538, PI. xxxi, 

 f. 6. 

 W. Tehuantepec, Sumichrast. 

 Geagras long-icaudatus Cope. Amer. Naturalist, 1884, p. 162. Enulius 

 murinus Cope, Bocourt, Miss. Sci. Mexique, p. 537, PI. xxxv, f. 9, 

 nee Copei. 

 West Tehuantepec, Sumichrast. 



PROC. AMER. PHILOS. SOC. XXII. 118, W. PRINTED MARCH 7, 1885. 



