•240 i MAJOR F. WALL, T.M.S., C.M.Z.S. 



times) . Again in all the other species the sutures made by the frontal with its con- 

 tiguous shields are subequal, or the frontc-parietal sutures are rather the longest. In 

 viperina the fronto-supraocular sutures are the shortest, and only half as long as the 

 fronto-parietals. The anterior ventrals in all the other species are barely twice as 

 broad as the last costal row. In this they are four times as broad or broader. I 

 think it extremely probable that osteological peculiarities will be found justifying its 

 separation from this genus and the creation of a genus apart. 



Hydrophis nigra. This is known from a solitary specimen which is now in the 

 British Museum. It was originally described by Anderson,' and subsequently figured 

 by Fayrer. It has the peculiar frontal and anterior ventrals typical of viperina and 

 agrees with this species in all other respects except colour, being black throughout. 

 (The specimen is now shrivelled, and the detail of some of the head shields in conse- 

 quence no longer discernible with certainty. Where I have had any doubt, however, 

 reference to Anderson's description from the fresh specimen has cleared it up). 



I reproduce Fayrer' s figures of this snake. From an artistic point of view the 

 figures leave much to be desired, but the two most important and clinching character- 

 istics of viperina (Schmidt) are well shown, and to my mind can leave no possible 

 doubt that the specimen is a melano-v i per in a. 



Description. — The neck is about half to three-fourths the extreme body depth. 

 Some of the head shields are very irregular in individuals, notably the postoculars, 

 temporals, supralabials, and posterior chin shields. Rostral, — the portion visible 

 above is about half (sometimes rather more or less) the suture between the nasals. 

 Prsef rontals, — touch no supra! abial. Frontal, — -twice to three times the 

 breadth of the supraoculars. Fronto-parietal sutures twice as long as the fronto- 

 supraoculars. Postoculars, — two usually (in four examples one). Temporals, — 

 very irregular, and usually broken up. (In four examples a fairly well- developed 

 anterior shield). Supralabials, — subject to much variation. Sometimes 7, 8, or 

 9. Often one or more of these shields from the third backwards divided. The third 

 and fourth, third, fourth and fifth, or fourth and fifth touch the eye. Infralabials, 

 — four, the last in contact with three or four scales behind ; the suture between the 

 first, equal to or greater than that between the anterior sublinguals. Marginals, — 

 one usually after the third infralabial (sometimes two). Sublinguals, — two fairly 

 well-developed shields, the fellows of each in contact. (In five examples the posterior 

 separated). Costals, — anterior 27 to 34 (usually 27 to 31), midbody 39 to 50 (usually 

 39 to 46) , posterior 35 to 45 ; imbricate anteriorly, juxtaposed posteriorly. Ventral s, — 

 235 to 267. Entire throughout, anteriorly four or five times, midbody and posteriorly 

 barely twice as broad as the last costal row. 



Habitat. — Persian Gulf to South China. It is remarkable that though not an 

 uncommon species, no specimen that I have seen has come from the Malayan Archi- 

 pelago. 



Colour. — This is very variable. Most specimens are adorned with from 26 to 37 

 dorsal bars or complete bands. I group the varieties as follows : — 



1 Proc. Zool. Soc. London, 1872, p. 399. 2 Thanatoph. Ind., 1874, plate sxv. 



