6 TKOCHOMOEPHID^. 



culato-planata, planorbiformi, depressa, fragili, oblique striatula 

 trauslucente, polita, olivaceo-cornea ; spira concaviiiscula, apice 

 foveolato, suturis profundis ; anfvactibus 4|, gradatim incres- 

 centibus, utrinque convexis, ultimo convexiuseulo, peripheria 

 subcarinata ; apertura valde obliqua, elliptico-lnnata ; peristomate 

 tenui, acuto, maginibus conniventibus, callo tenui jiinctis. 



" Diam. uiaj. 6, uiin. 5, alt. 1^ mill." 



Hah. Ceylon : Eort M'Donald (Layard). 



7. Trochomorpha percompressa, Blanford. 



Hdix (Sivclla) jJcfcompressa , Blanford, P. Z. S. 1869, p. 448. 

 Trochomorpha jjerconipressa, Nevill, J. A. S. B. 1877, p. 15; ibid., in 



Anderson, Zool. Res. Exped. W. Yunnan, i, 1878, p. 873, pi. 80, 



fig. 7 ; ibid.. Hand List, i, 1878, p. 56 ; ibid., J. A. S. B. 1881, pt. 2, 



p. 133, pi. 5, tig. 22. 

 Helix {Trochomorjiha) percompressa, Tryon, Man. Couch, ser, 2, iii, 



1887, p. 84, id. 16, figs. 8-10. 



Original description: — "Testa aperta et pervie umbilicata, 

 perdepressa, lentieularis, tenuis, cornea, acutissime cariiiata, 

 nitida, striis increment! oblique curvatis notata. Spira fere plana, 

 apice vix exserto, sutura impressa marginata. Anfr. 5, convexi, 

 ultimus carina mediana acuta utrinque compressa instructis, circa 

 umbilicum tumidior, non descendeus. Apertura parum obliqua, 

 securitormis ; peristoma tenue, rectum. 



"Diam. maj. 12, miu. 10|, axis 3 mill." 



Hah. Burma : Bbamo (Anderson) • 2nd Iravaddy Defile (An- 

 derson). 



Subgenus VIDENA, H. 4- A. Adams. 



Videna, H. & A. Adams, Gen. llec. Moll, ii, 1858, p. 15 (as sub- 

 geiuis of Zo7utes), proposed in lieu oi Discus, Albers, 1850, not of 

 Fitzinger, 1833; Martens, Preuss. Exp. Ost-Asien, Zool. Theil, ii, 

 1867, p. 247 (second group of Trochoviorpha) ; Pilsbrv, Man. 

 Conch, ser. 2, ix, 1893, p. 3. 



Type not indicated. Eirst species HeliA' heclciana, Pfeiffer. 



Range. Islands East of British India, Malaysia, China, Japan, 

 Philippines, New Guinea. 



Original description : — " Shell widely umbilicated, discoidal, 

 keeled, flat, or slightly elevated above, convex at the base, last 

 whorl slightly deflexed at the aperture; peristome simple, acute, 

 or slightly marginate, the margins arcuated." (Adams.) 



8. Trocliomorpha andamanica (Ncvill), Godwin-Austen. 



Discus andamanica (Xevill), Godwin-Austen, P. Z. S. 1895, p. 448. 

 Trochomorpha ( Videna) andamanica, Fulton, A. M. N. H. ser. 6, 

 XX, 1897, p. 212, pi. 6, fig. 4. 



" Shell subcircular, light yellowish brown ; umbilicus \\ ide 

 funnel-shaped and sharply angled; whorls 6|, slowly increasing, 



