VERTEBRATA FROM MADAGASCAR. 487 



37. Natrix lateralis (Dumeril & Bibron). 



A considerable series from the Eastern Forest and two from the 

 swamps near Didy. 



38. Natrix sexlineatds (Gunther). 



Eight examples of this rare species from the Eastern Forest. Boett- 

 ger includes this species and N. grandidieri both in N. dolichocercus . 

 Boulenger, however, has shown (P. Z. S., 1915, p. 373) that in this 

 he was entirely wrong. 



39. Lioheterodon madagascariensis (Dumeril & Bibron). 

 A fine series from Morondava, Didy, and the Eastern Forest. 



40. Lioheterodon modestus (Giinther). 



Three examples from the Eastern Forest. Boulenger (P. Z. S., 

 1915, p. 376) says that in this species the internasals are in contact 

 with the frontal. In 1893, however, he figured the opposite, i. e. 

 prefrontals separating the internasals from the frontal (Cat. snakes 

 Brit, mus., 1893, 1, pi. 18, fig. 1). Among these specimens two agree 

 with the figure, while the third, evidently injured on top of the head, 

 has the prefrontals barely touching the frontals and the internasals 

 just separated. 



41. PsEUDOXYRHOPUS quinquelineatus (Gunther). 

 A single typical example from Didy, eastern Madagascar. 



42. Eteirodipsas colubrina (Sclilegel). 

 Fifteen from the Eastern Forest and two from the swamp at Didy. 



43. MiMOPHis mahfalensis (Grandidier). 



Nine from the Eastern Forest and one from 14 kilometers south of 

 Miandrivazo. 



