A MONOGRAPH OP THE SEA-SNAKES {HYBUOPU1INM ). 205 



H. leptodira is known from a single specimen, described by Cantor, 1 and now in 

 the British Museum. The description given by Mr. Boulenger exactly accords with 

 that given by him of fasciata (Schneider) y except that leptodira has 58 scales round the 

 body. That authority counts the scales differently from me, taking them round the 

 extreme body girth. I count them in three definite situations as already stated in my 

 prefatory remarks under " costals." The scales in these three places number 30, 50 and 

 47, and the snake accords perfectly in this, as in all other respects, with typical examples 

 of fasciata. In three other specimens I find them 50 in midbody, and in three 49. 



H. brookii (Giinther).- -I have examined the only known specimen which is in the 

 British Museum. The description of this specimen in Mr. Boulenger's catalogue ' 

 compared with that of fasciata shows one solitary difference, viz., in the length of the 

 frontal which in brookii equals its distance to the end of the snout, but in fasciata 

 equals its distance to the rostral only. I find, however, that in many speci- 

 mens of fasciata the frontal equals its distance to the end of the snout. Even if it 

 did not, so extremely slender a distinction occurring in a solitary individual should 

 deter one from ranking it as a species. I think I am nearly accurate if I say that 

 probably no individual is found of any species exactly in accord with the type, and 

 if one were to create species on differences as slender as has here been the case, almost 

 every individual would have equal claim to such rank. I have examined the type 

 with many specimens of fasciata, and can find nothing to separate them 



Distira rhombifer. — A single example only of this is known, described by Mr. 

 Boulenger 4 from a specimen now in the British Museum. He remarks upon its close 

 affinities to fasciata, and separates it on the broader rostral, larger number of body 

 scales (55) and the colour. The first distinction affecting the rostral is a very minute 

 one and affects a shield which in breadth is subject to much variation in individuals 

 of the same species. I find other specimens which I consider fasciata where it is rela- 

 tively quite as broad. The scales in this specimen I count 32, 49 to 51, and 45 in 

 anterior, mid, and posterior body. It thus accords perfectly with other specimens 

 of fasciata in the British Museum. As regards colour there are at least four other 

 examples of fasciata in the British Museum exactly similar, i.e., with rhombs dorsally 

 instead of complete rings. I see no difference between this and fasciata. 



H. melanocinctus. — Last year I described as a new snake s what I considered 

 at the time a very definite species, but which now I must regard as a somewhat 

 aberrant fasciata. I took my original view because the specimen had only 25 rows of 

 scales anteriorly, the prsefrontal failed to touch the second supralabial, and the scales 

 were imbricate posteriorly. Though the anterior scales are unusually low, I find a 

 a specimen of fasciata in the British Museum with 26, viz., the type of Giinther's 

 atriceps, I find the prefrontal does not touch the second labial in four other specimens 

 I have seen, and the scales I observe are imbricate posteriorly, contrary to the rule, 



1 Trans. Zool. Soc. Lond., 1840, p. 311, and plate lvi. 3 III, 1896, p. 282. 



2 Proc. Zool. Soc. Lond., 1872, p. 597. * Ann. Mag. Nat. Hist., 1900, p. 306. 



5 Memoirs, As. Soc. Bengal, 1906, p. 287. 



