MOLLUSCA OF INDIA. l&T 



The material used in the following descriptions was derived from 

 several sources : the most reliable as regards this species from 

 Dr. W. T. Blanford, collected by him at Darjiliiig and preserved in 

 spirit; also the shells in his collection (Plate CVl. fig. 1). When 

 in Calcutta in 1877, Mr. G. Nevill placed in my hands a shell 

 identified by him as M. sequcLv, which he had just received alive 

 from Darjiling, sent by Colonel Mainwaring. I made a careful 

 description of the animal at the time in my note-book, which I give 

 below ; but unfortunately, to make it complete, 1 did not retain the 

 shell. At the same time T made a drawing, showing the form and 

 position of the right shell-lobe (fig. 3) and of the extremity of the 

 foot (fig. 3 6). In Nevill's ' Hand-list,' p. 23, there is a note on the 

 animal by ilanford : "A true Macrochlamys ; animal pale, with 

 back and tentacles black. — W. T. B." Next I had from Damsang, 

 east of the Teesta Eiver, some shells very similar in general 

 appearance, but smaller than the type shell, which I at first took 

 to be sequax ; but on closer examination these diff'er in several 

 particulars sufficiently to constitute a new species. 



Description of the living animal received from Darjiling : — 



Living animal of scquax'? pale ochraceous throughout, including 

 the mantle ; a greenish tint on the neck, pinkish towards extremity 

 of foot. Tentacles dark, from the base of which run two parallel 

 dark lines towards the aperture. From the base of the lower 

 tentacle a groove runs diagonally up towards the posterior of the 

 neck. Mantle slightly reflected over the peristome all round and 

 to a greater extent on the lower margin, where on the left side, at 

 about 0-35 inch or 9 mm. from the umbilicus, a small tongue-like 

 process (the left shell-lobe) is given off laterally. Close to the 

 upper angle of the aperture a well-developed right shell-lobe 

 (tigs. 3, 3 a) is given ofi" horizontally and is often extended for 

 •2 inch or 5 mm., but never above the periphery of the shell. The 

 posterior part of the foot (in this example) was ornamented with 

 four diagonal lines, which meet above in an angle ; the general 

 surface rugose ; the peripodial margin broad and defined. The 

 mucous gland (fig. 3 h) overhung by a curved lobe. Length : head to 

 shell 0-6 inch, extremity of foot to shell 0"7o : total nearly 2 inches. 

 Eye-tentacles long and slender, 0"-l inch. 



The following notes were made when dissecting Dr. Blanford's 

 specimen: — Shell (fig. 1): sculpture smooth, with indistinct fine 

 spiral striation. Animal unicolor in spirit ; peripodial margin 

 broad. The right shell-lobe is a well-developed tongue-like 

 process ; the left shell-lobe small. The horn above the mucous 

 gland of moderate size, blunt. Generative organs : penis (fig. 1 a) 

 rather long, with a long kalk-sac. The retractor muscle is short 

 and thick, given off from quite a large coiled caecum. The 

 spermatheea is very long. The amatorial organ also very long. 

 The radula (figs. 1 c,ld) was extracted nearly complete ; formula : 



33 . 2 . 12 . 1 . 12 . 2 . 33 



47 . 1 . 47 



