170 Mr. N. Rosen on the Snakes in the 



17. Tropidonotus ordinal us, L., var. infernalis. 

 Oregon. 



18. Tropidonotus ordinatus, L., var. sirtah's. 

 Oregon. 



19. Tropidonotus sauritUy L. 



Total length of one specimen 970 mm. : tail 290. 

 North America. 



20. Tropidonotus natrix, L. 

 •Sweden. 



21. Tropidonotus trianguUgerus^ Boie. 

 Java, Sumatra. 



22. Tropidonotus piscator^ Sclin., type C 



Scales sometimes feebly keeled or nearly smooth, reminding 

 on<' of Tr. Sancfi-Johannis {see Boul. Cat. Snakes, i. p. 230j. 

 Java. 



23. Tropidonotus tesseUatus, Laur. 

 South Europe. 



21. Tropidonotus viper inus, Latr. 

 Algiers. 



2o. Tropidonotus Clarkiij B. & G. 



26. Tropidonotus tigrinus, Boie. 



27. Tropidonotus vittatus^ L. 

 Java. 



28. Tropidonotus suhminiatus, Schleg. 



Some specimens with third and fourth upper labials entering 

 the eye. 

 Java. 



29. llelicops angulatus, L. 



30. llelicops modestus, Gthr. 



31. IJelicops leopardinus, Schleg. 



Tiie last two species differ from the descriptions by not 

 having any hypapophyses in the posterior region of the dorsal 

 column. In //. leopardinus, Schleg. (which is represented 

 in the Lund Museum by a single specimen), the lower surface 

 of the dorsal vertebra3 in the posterior region has a lower 

 keel (text-fig. 1, a), without any crest or tuberculc projecting 



