A MONOGRAPH OF THE SEA-SNAKES (HYDBOPHIINM). 213 



the fore, and midbody being repectively 28, and 33 to 34. I hold that the costals carry 

 greater weight than the postoeulars and temporals. The latter, in this specimen, con- 

 form to the generality of examples of cyanocincta, but these shields being subject to some 



ABC 

 Fig. 23. — Distira longiceps. After Giinther, Rept. Brit. Ind., pi. xxv, fig. O. 



variation in both these forms prompts me to regard them as abnormal in this instance. 



The one other departure from the normal mentioned by Mr. Boulenger is the 

 juxtaposed character of the posterior costals. Personally I found it extremely hard 

 to decide for myself whether these scales were imbricate or juxtaposed, and finally 

 decided they were juxtaposed dorsally and subimbricate ventrally. I do not attach 

 sufficient weight to this character to consider it should justify separating this form from 

 spiralis, and even granting that the scales are juxtaposed ventrally behind, the fact 

 that Mr. Boulenger himself in one case at least, viz., fasciata (Schneider), places speci- 

 mens with the scales imbricate, together with others that are juxtaposed, makes it 

 probable that a similar deviation from the normal may be expected in other species. 



wrayi (Boulenger). — As recently as 1900 Mr. Boulenger described this as a new 

 species from a specimen sent from Perak. I have examined the three available 

 specimens so labelled in the British Museum, the only ones known. One of them is 

 so labelled by an oversight, for it is obviously a very typical specimen of gracilis (Shaw). 

 Of this there is no possible doubt. The other two I examined beside specimens of 

 spiralis and brugmansii, but failed to detect in them one feature by which they could 

 be distinguished. One of them is peculiar in having no marginals. Referring to 

 Mr. Boulenger's description of D. wrayi} and comparing it with his description of 

 brugmansii in his catalogue," I find they completely agree, except in two extremely 

 minute details, viz., the length of the frontal which it is claimed is rather shorter in 

 wrayi, and carination which is more pronounced in wrayi. Such minute differences, 

 especially affecting features which are subject to considerable variation, appear to me 

 very unconvincing. I cannot even agree that the differences claimed are any more 

 noticeable than is seen in certain examples of brugmansii in the British Museum. 



floweri (Boulenger). — This is known from two specimens only, both in the British 

 Museum. Though placed by Mr. Boulenger with his genus Hydrophis, the post- 

 maxillary teeth are grooved, and had this circumstance been noticed by him, I cannot 

 but think he would have referred them to brugmansii. 'From this species I can only 

 separate it by (1) the absence of marginals, and (2) the failure of the prefrontal to 

 meet the second supralabial. The absence of marginals is remarkable, the only other 

 instance of these shields being wanting among the specimens I consider alike being 



1 Ann. and Mag. Nat. Hist, v, 1900, p. 307. 2 HI, p. 293. 



