100 BURMA, ITS PEOPLE A.XD PRODUCTIONS. 



throughout or noarly so, and nearly all having some raised scnlpturo across the 

 ■whorls, and all, too, distinguished by a constriction at some distance behind the 

 mouth, but in the ovate and turritcdly ovate forms {Biplommatina) this constriction 

 is more or less concealed by the last whorl. 3. Puphihue, ovate or turrited shells, 

 usually of one colour and often very richly coloured, destitute of constriction and as 

 a rule of sculpture. They are usually larger shells than Uiphinmaiinidca, many of 

 ■which are very minute. 



The genera of Cyclophorinm found in Burma are four in number. Cyclophorm 

 comprises discoid and turbinate shells, the former simple, coiled in the form of a disc 

 and flat above, the latter conical above and rounded belo'w (the spire being always 

 considered the upper part and the mouth the lower). In this genus the spire is 

 never much raised, the aperture is circular, destitute of notches, or projecting 

 processes, and usually thickened, and the operculum is horny and nearly fiat. In 

 the subgenus Scnbriiia there is a rough epidermis, the operculum is thickened, and 

 the margins of the whorls of which the operculum is composed consist of narrow free 

 lamella3 ; the sliell is depressed and subdiscoidal. In J'tiroci/dits there is a small 

 ■wing-like process covering the corner of the aperture where the peristome (or edge 

 of the shell surrounding the mouth) joins the last ■whorl, and beneath this ■wing there 

 is a deep notch in the shell. Spiraciihun resembles Plerociidus, but has in addition 

 a tube o])en at both ends, at one end into the ■whorl and at the other end into the air, 

 attached to the last whorl close to the suture a little behind the mouth. In both 

 Pterocijclus and Spiracidiim the operculum is horny, convex or flat, thick, ■\vith the 

 edges of the whorls free. In Rhiostoina the mouth is free and furnished with a 

 subtubular process projecting upwards in front; there is also a sutural tube, as in 

 Spiracuhim ; the operculum is shelly, very thick, and deeply concave inside. Lepio- 

 poma is a conical shell, rather thin, ■with a thin horny operculum. Laguclieilua is 

 subconical, and like a small Ci/dophorns, but with a small vertical groove across the 

 peristome, close to the place ■where it joins the last whorl. 



The Diplommatininm comprise Ahjcmus, subdiscoidal or subconical, usually of 

 small size, ■with a very marked constriction some distance behind the mouth, and, in 

 many cases, strong ribbing transverse to the whorls behind the constriction. There 

 is also a small tube running back from the constriction, for a greater or less distance, 

 along the suture, opening into the whorl in front and closed behind. Biplommatina 

 is subfusiform, elongately ovate, of minute size, ■with a sutural tube, generally white 

 or amber-coloured, and usually with vertical ribs. Clostophis is only known from one 

 specimen ; it resembles Diplommatina, except that the last whorl is free and descending. 

 It is far from certain that the soKtary type is anything but a distorted Bipltjmmatina. 



The Pupinina include four genera, but the species are few in number. Megalo- 

 mastoma is a turrited thick shidl, about an inch in length, with a circular aperture 

 destitute of grooves or tubular processes. The operculum is thin and horny. The 

 shell has a thick brown epidermis. IIi/lnci/Ktis is a solid shell, egg-shaped, flattened 

 above the aperture, which is round and destitute of grooves or tubes. The operculum 

 is shelly, multispiral outside, paucispiral within. This genus is the largest of the 

 Pupinina;, being nearly one and a half inches in length and four-fifths of an inch in 

 diameter. Pupina and Raphauliis are smaller shells, very highly polished and ovate 

 in form ; in the first the peristome is marked by deep transverse incisions, one above, 

 the other on the left side ; in the second there is a tube opening in the peristome 

 itself, close to its junction with the last whorl, and running to a short distance outside 

 the shell. 



The Hclicinidx differ much in structure from the other families of land shells. 

 The operculum is not round, but lunate, or semicircular, shelly, transparent, devoid 

 of spiral structure, and in one genus, Hydroccna, furnished with an internal process. 

 It should here be remarked that in all probability Ilelicina and Hydroccna really 

 belong to different families. Ilelicina is a lenticular, smooth, or nearly smooth, form, 

 ■whereas Ilydrocena (^Georissa) is subturrited or subconical, with rounded whoils, 

 and, as a rule, with raised spiral sculpture. The few Burmese forms of ITelicina are 

 small, none exceeding one-third of an inch in diameter, but the species of Georissa 

 are minute. 



