376 JOURISAL, BOMBAY NATURAL HIST. SOCIETY, Vol. XXIII. 



part, just as one sees other labials preceding them divided in some speci- 

 mens. {Vide figures.) In all the foetuses the bands (55 to 68 in number) 

 are complete. The first 2 to 5 bands are confluent ventrally, the succeed- 

 ing ones discrete. All are somewhat dilated vertebrally, and about the 

 same width as the spaces at midcosta. In some a light horse-shoe is more or 

 less distinct on the head, passing anteriorly across the prsefrontals, and 

 posteriorly over the eye through the temporal region. In the adults the 

 bands taper ventrally or fade at about midcosta, but though the black 

 fades the bands are usually more or less discernible as such. The post 

 maxillary teeth are usually 7 in number, sometimes 6, and in one examples. 



Figs. 6 to 11 inclusive are taken from the foetuses extracted from No. 

 861 and are specially interesting on this account. The parent has the head- 

 shields on both sides arranged as in fig. 13. Fig. 6 shows the normal 

 shielding of this species, the first 5 labials entire, the 6th and 7th divided, 

 and the 3rd, 4th and 6th bordering the eye. Fig. 7 shows a divided 5th 

 labial. Fig. 8 shows a confluence of the usual 4th and 5th labials. In 

 fig. 9 the lower parts of the 4th and 5th labials are united. Fig. 10 shows 

 confluent 4th and 5th labials and an entire 6th labial. In fig. 11 the Srd 

 labial fails to touch the eye, and the upper part of the 7th is confluent with 

 a lower temporal. Fig. 12 has all the labials from the 3rd divided, and 

 fig. 13 (the right side of the same specimen) has the 5th divided, but not 

 the Srd or 4th. In fig. 14 the 3rd and 5th labials are entire, but not the 

 4th. Fig. 15 shows a confluence between the upper part of the 4th, and an 

 entire 5th labial. The upper part of the 7th is joined with a lower 

 temporal. 



As a result of many years' special study of the HydrophiincB, I find I can 

 only recognise as distinct with certainty those species from the Indian seas 

 that are enumerated. 



Hydkophis jbkdoni (Gray). 



Two specimens, one adult and one young, are the only representatives of 

 this species. The temporal is confluent with the 6th labial as is usual, and 

 the labials are all entire. The postmaxillary teeth number 9 in the adult. 



Enhydris curtus (Shaw). 



There are 11 examples, the longest measuring 2 feet 8 inches. Most are 

 juvenile and one in a bad state of preservation. The same variation in the 

 labials, postoculars and temporals that one sees in E. valakadyn and 

 H. cyanocinctus is also very marked in this species. The anterior 4 or 5 

 labials are usually entire, and the 3rd and 4th usually border the eye. In 

 one young specimen the bands are complete, but in the others the bands are 

 replaced by bars that disappear about half, or two-thirds down the side of 

 the body. In adults the bars are less distinct, and less defined. The post- 

 maxillary teeth are usually 5 in number, less commonly 4 or 3. Fig. 16 

 shows the normal arrangement of shields. Fig. 17 (the right side of the 

 same specimen) sho^vs a divided 4 labial and the upper part of the 7th 

 labial confluent with the lower temporal. Fig. 18 shows a complete con- 

 fluence of the 3rd and 4th labials and a confluence of the lower part of 

 the 6th labial with the 5th labial. The postoculars are also confluent. 



Enhydrina valakadyn (Boie). 



Of the 13 representatives the two largest (both females) measure 3 feet 

 11 inches and 4 feet 3| inches. The latter has a girth of 6f inches. The 

 postoculars, labials and temporals present very great variations. The sub- 

 linguals are poorly developed, and when recognisable as such are separated 



