84 ZONITIDyE. 



123. Macrochlamys opipara, Goihcin-Austen, MoJ. hid, i, 1883, 

 p. 108, pi. 23, fig. 6. 



Shell perforate, subglobosely depressed, less thin than most 

 species of the genus, smooth and polished above and below, but 

 with minute fine and dose, shallow, longitudinal, impressed lines 

 throughout, yellowish chestnut (horny in young specimens) ; spire 

 low, conoidal, suture slightly impressed ; whorls 6, convex, the 

 last considerably broader, rounded at the periphery, moderately 

 tumid beneath; aperture slightly oblique, roundly lunate ; peri- 

 stome thin, straight, with a distinct thickening a short distance 

 inside the lip, columellar margin curved, obHque, reflected above, 

 partly closing the perforation. 



Major diam. 26|, min. 24, height 15 mm. 



A smaller specimen measures i7x 14^ X 12|^. 



Hah. Sikhim: Kursiong, 4000'; Darjihug, 7000'; Tonghu, 

 10,000'. 



Apparently not common. The adult form is one of the hand- 

 somest shells in the genus. Immature specimens have long been 

 known and were regarded by Benson as a variety of ill. Juhrica. 



[124. Macrochlamys damsangensis, Godtvin- Austen, Mol. Ind. ii, 

 1907, p. Ub, pi. 105, figs. 2-2/. 



Shell depressedly globose, scarcely perforate, glassy ; sculpture 

 indistinct ii-regular longitudinal strise, but quite smooth in places ; 

 colour rich sienna-brown, pinkish inside the aperture ; spire 

 depressed; suture shallow; whorls 4 (not quite fully grown), 

 rather tumid and rapidly increasing ; aperture subvertical, ovate, 

 the peristome on outer margin nearly the curve of a true circle. 

 Columellar margin weak, subvertical, scarcely reflected. 



Size: maj. diam. 18-5, min. diam. 14-7; alt. axis 6*4, alt. body- 

 whorl 6-8 mm. 



Hah. Damsang Peak, Daling District, Bhutan Duars. 

 Animal. Has the typical shell-lobes of MacroMamys. The 

 specimen dissected was much contracted and hardened by the 

 alcohol, so that the mucous gland and lobe above both appear 

 small. The sole of the foot is strongly divided into middle and 

 lateral areas. The peripodial groove is conspicuous and the 

 maro-in broad. The membrane covering the pulmonary cavity is 

 of a dark green colour, closely speckled, and above the renal organ 

 and heart "is quite black. The specimens were evidently taken in 

 the cold season, for the generati\'e organs were found to be ex- 

 ceedingly small and contracted and in trying to get thera out were 

 broken, yet sufficient was seen to show there was an amatorial 

 organ and the general form of the penis. This shows a long kale- 

 sac or flagellum and a convolution where the retractor muscle is 

 «iven ofl: ; it therefore agrees with the typical form of the caecum 

 ui this genus, although its general form must be much altered 

 and swollen during the season of reproduction. 



