in the Collection of the British Museum. 29 



Euophrys modestus (Gtlir.). 



Specimens of this snake have been obtained from Paraguay 

 and Buenos Ayres. It is not a Chinese species. 



Leptognathus. 



The snakes of this genus feed chiefly on slugs, like the 

 Indian species of the family of Amhlycephalidce. 



Mr. Cope has given a very lucid synopsis of the species of 

 this genus (Proc. Philad. Acad. 1868, p. 107), by which their 

 determination is much facilitated. I think he has attached 

 too great a value to the arrangement of the shields between 

 the eye and nostril and the number of labial shields ; but the 

 limits of variation, which differ almost in every species, can 

 only be ascertained by the examination of numerous examples. 



Leptognathus Mikanii (Schleg.). 



The British Museum possesses several examples from 

 Western Ecuador, one of which agrees perfectly with Lepto- 

 gnathus oreas of Mr. Cope (Proc. Philad. Acad. 1868, pp. 108, 

 109), whilst the others lead up (with regard to pholidosis) to 

 the typical eastern form. All these western specimens, how- 

 ever, have the abdomen extensively mottled and chequered 

 with black. None of the other structural characters which 

 were supposed to be distinctive being constant, I refer these 

 specimens, with L. oreas, to L. Mikanii. One of our Ecuador 

 specimens approaches a prettily coloured variety from Tehuan- 

 tepec, from which the following notes are taken. 



Posterior frontals large, not entering the orbit. Vertical as 

 broad as long, with an obtuse angle behind. Loreal entering 

 the orbit ; another well-developed anteocular above it ; two 

 postoculars. Eight upper labials, the fourth and fifth entering 

 the orbit. Temporals 24-3(2)4-3. Three pairs of chin- 

 shields subequal in size, as broad as long ; a pair of lower 

 labials form a suture together in front of the chin-shields. 

 Ventrals 188 ; anal entire ; subcaudals ca. 85. Yellowish, 

 with numerous narrow black cross bands, 44 on the trunk and 

 23 on the tail, as broad as the interspaces of the ground- 

 colour ; each more or less completely divided into two by a 

 yellow transverse line, which is broader within the anterior 

 black bands than within the posterior. The bands do not ex- 

 tend on the belly, which is chequered with black. Upper 

 parts of the head black, finely mottled with yellow. 



The specimen is 12 inches long, tail 3 inches. 



