6 THOCHOMOEPHID.E. 



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

 translucente, polita, olivaceo-cornea ; spira concaviuscula, apice 

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

 centibus, utrinque convexis, ultimo convexiusculo, peripheria 

 subcarinata ; apertura valde obliqua, elliptico-limata ; peristomate 

 tenui, acuto, maginibus coimiventibus, callo tenui junctis. 



" Diam. maj. 6, min. 5, alt. 1| mill." 



Hob. Ceylon : Port M'Donald (Lai/ard). 



7. Trochomorpha percompressa, Blanford. 



Helix (Sivella) percompressa, Blanford, P. Z. S. 1869, p. 448. 

 Trochomorpha percompressa, 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, fig. 22. 

 Helix (Trochomorpha} percompressa, Tryon, Man. Conch, ser. 2, iii, 



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



Original description'. "Testa aperta et pervie timbilicata, 

 perdepressa, lenticularis, tenuis, cornea, acutissime carinata, 

 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 turnidior, non descendens. Apertura parum obliqua, 

 securiformis ; peristoma tenue, rectum. 



"Diam. maj. 12, min. 10J, axis 3 mill." 



Hob. Burma : Bhamo (Anderson} ; 2nd Irawaddy Defile (An- 

 derson}. 



Subgenus VIDENA, //. $ A. Adams. 



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

 genus of Zonites), proposed in lieu of Discus, Albers, 1850, not of 

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

 1867, p. 247 (second group of Trochomorpha) ; Pilsbry, Man. 

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



TYPE not indicated. First species Helix leckiana, 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 ; peristorne simple, acute, 

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



8. Trochomorpha andamanica (Nevill), Godwin-Austen. 



Discus andamanica (Nevill), 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 wide 

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



