A MONOGRAPH OF THE SHEA-SNAKES (HYDROPHIUNA). 205 
H. leptodiva is known from a single specimen, described by Cantor,!' and now in 
the British Museum. ‘The description given by Mr. Boulenger exactly accords with 
that given by him of fasctata (Schneider), except that /eptodira 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. brooku (Gunther). -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 fascrata shows one sotitary difference, viz., in the length of the 
frontal which in brook 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 
Distiva vhombifey.—A single example only of this is known, described by Mr. 
Boulenger* 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 fascvata in the British Museum exactly similar, 7.e., with rhombs dorsally 
justead of complete rings. I see no difference between this and fascvata. 
H. melanocinctus.—\Last year I described asa new snake’ 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 prefrontal 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 fascrata in the British Museum with 26, wz., the type of Gitinther’s 
atriceps, I find the preefrontal 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 tvi. 3 IIT, 1896, p. 282. 
2 Prac. Zool. Soc. Lond., 1872, p. 597. + Ann. Mag. Nat. Hist., 1900, p. 306. 
5 Memoirs, As. Soc. Bengal, 1906, p. 287. 
