210 Records of tin Indian Museum. [Vol. VIII, 



height towards the posterior end. The margin of the mantle 

 (perinotum) is thin, sharp and inflexed, but not wrinkled. The 

 margin of the mantle-hood is entire. The mantle at the extreme 

 posterior end of the body is inflexed, so that the posterior end of 

 the foot projects below and a little behind the posterior margin 

 of the mantle, which is thus placed in front and on the ventral 

 aspect of the posterior end of the mantle. 



The head is distinctly separate from the anterior end of the 

 foot. The proboscis, which is protruded in the larger of the two 

 specimens, is cylindrical, and ends in a blunt tip with the triradi- 

 ate oral aperture in the centre. The ommatophores are short, 

 stout and faintly annulated ; they seem to be non-retractile. The 

 lower tentacles are stout and short, being narrower at the base than 

 at the tip. They are fused with the precephalic flap beneath 

 except at the extreme anterior end for about 'i cm. .They are 

 bounded externally by a deep sulcus, which extends from the base 

 to the ventral aspect of their free anterior end. Each precephalic 

 flap is a continuation forward of the head from the ventral aspect, 

 and is united to that of the other side by a thin flattened band of 

 integument above the mouth and beneath the ommatophores. The 

 anterior and outer borders of the flap are convex, the inner one is 

 nearly straight. The antero-external angle is acute but rounded, 

 and the antero-internal angle is obtuse. 



A small triangular process of integument is placed above the 

 foot at its antero-lateral aspect, being continuous at its outer side 

 with the lateral surface of the foot above the sole and in front of 

 the attachment of the mantle to the side of the foot. The inner 

 end of the process (corresponding to the apex of the triangle) is 

 connected to the ventral surface of the precephalic flap at the outer 

 side of its base by a thin band of integument. Below, the process 

 is separated from the dorsal aspect of the anterior end of the foot 

 by an obHque groove extending downwards and outwards from the 

 inner side. These two triangular processes form the lateral boun- 

 dary of the crescentic aperture of the pedal gland. 



The foot is wide in front and tapering behind. It is widest 

 at the junction of the anterior one-fourth and posterior three- 

 fourths of its length, being a little constricted just in front of it. 

 The anterior end is truncated and slightly concave. The posterior 

 end is tapering but rounded, and extends a little downwards and 

 backwards beyond the inflexed posterior margin of the mantle, 

 but terminates in front of the extreme posterior end of the latter. 

 The sole is lobulated in its anterior three- fourths, but smooth in 

 the posterior one-fourth of the length. 



Colouration. — The mantle is light straw-coloured, being dirty 

 in its upper ^ two- thirds. The surface of the mantle, in its upper 

 two-thirds, is marked with an irregular network of dark blue lines, 

 mostly arranged in two sets passing diagonally in opposite 

 directions and crossing one another at obtuse angles (on the dorsal 

 and ventral aspects). The points of intersection become thickened 

 to form elongated dark blue dots varying from -05 to "i cm, in 



