MOLLUSCA OF INDIA. 



265 



Macrochlamts politula, Gr.-A. (Plate CXX. figs. 3-3 d.) 



LocaliUj. Diyung Valley, Singpho Hills. No. 2087 B.M. Coll. 

 The two specimens now referred to, neither fully grown, were 

 obtained by Mr. M. Ogle. The species was described in Vol. I. 

 p. 107, PlateXXIII.fig. 3, asavariety of il/.7m?'(ZwM'A-ei. Itwasfroin 

 Upper Assam, also from Brahmakund on the Lohit Brahmaputra 

 Eiver. The two specimens on page 107, under hardwkhei var., 

 I consider should be included. The animal was not then known. 

 The two specimens were found together with M. vesica ^ and 

 preserved m alcohol ; the very different coloration of the animals 

 distinguish them at once, M. vesica being of the same colour 

 throngliOLit with no markings. 



Animal. A black quadrangular patch near the rectum (fig. 3), 

 which is bordered for a long distance with large spots of same 

 colour, with another series in the middle line of the branchial 

 wall, up to and as far as the kidney, sparsely and finely spotted 

 ou the left side of the visceral sac (fig. 3 a). Right shell-lobe 

 (fig, 3) moderately long, broad at base, given off from thft right 

 do'i-sal lobe. The left sheli-lobe (fig. 3 a) very narrow and small, 

 rising from a broad triangular base. The left dorsal lobe is in 

 two distinct parts, the posterior elongate narrow with free ends. 



The generative organs (fig. 3 h) are of the true Macrochlamys 

 type, but differ from those of M. hardwickei in the form of the 

 penis, the kale-sac of which is quite short, and there is a distinct 

 terminal knob at the anterior end. The principal difference in the 

 genitalia of 31. politula, compared with that of M. hardwiclcei of 

 Calcutta, is that the kale-sac of the penis is very short in the 

 former, while it is unusually long in the latter {vide Plate XXVIII. 

 Vol. I. figs. 1 rt, 1 h). The amatorial organ is long, cylindrical, 

 gradually tapering into a long retractor muscle, the anterior end 

 bluntly rounded. 



The radula (fig. 3 d) has the formula 



38 . 1 . 12 . 1 . 12 . 1 . 38 

 or 51 . 1 . 51. 



Central and admedian as usual, the marginals unevenly bicuspid, 

 the inner point much the longest, those on the extreme edge very 

 minute. 



Jaw (fig. 3 c) arched, narrow, with a slight central projection, 

 differing much from that of M. liardwickei. 



Macrochlamts atjoigyrata, G.-A., MS. (Plate CXXXI. 

 fig. 11 ; Plate CXXXII. fig. 8, animal.) 



Locality. Nemotha Hill (Trigonometrical Station), Cachar (J. 

 Wood-Mason). 



Shell depressedly conoid, narrowly perforate, thin, glassy, 

 shining; sculpture very fine microscopic longitudinal striation, 

 not seen on the apical whorls ; colour pale straw or ochraceous, a 



