AEIOPHANTA. 



43 



72. Ariophanta (Xestina) chenui, Pfr. (Helix) Zeitschr. Mai. 1847, 

 p. 145; id. (Helix) Man. Hel. i, 1847, p. 438; H. 8,- T. (Helix) 

 C. I. 1876, pi. 25, fig. 1, pi. 27, flg. 4; Nev. (Nanina-Hemi- 

 plecta) Hand-l. i, 1878, p. 47; Godwin- Austen (Nilgiria), Mol. 

 Ind. ii, 1898, p. 124, pi. UO, figs. 1-i) (aniiual and anatomy), pi. 98, 

 fig. 3 (sculpture). 

 Hemiplecta simoni, Jotisseaume, Mem. Soc. Zool. Fr. vii, p. 282 

 (1894). 



Shell openly perforate, depressed, rather thin, lulvous, with a 

 narrow pale hand, often indistinct, ahove the periphery, and a 

 darker, ill-defined, rufous-brown band, fading away beneath, 

 below the same ; sculpture decussated, striae of growth and 

 impressed spiral lines occurring throughout, the upper surface of 

 the last whorl marked with shallow, irregular, slightly oblique 

 ridges and furrows, resembling hammer-marks on metal ; spire 

 low, convex, suture slightly impressed, more towards the mouth ; 

 whorls Ak, flattish above, the last more convex, slightly angulate 

 at periphery, more swollen below; aperture oblique, ovately 

 lunate ; peristome slightly thickened. 



[The right shell-lobe is represented by a very small flap, situated 

 near the respiratory aperture; this flap is an expansion on the 

 dividing line of the dorsal lobe and narrows backward towards 

 the posterior margin of the mantle-zone, which, on the body- 

 whorl side and viewed from the inside (that is, the surface next 

 the shell), is seen to form a distinct band with an equal breadth 

 of 2| ram. contracted. Compare this also with the riglit sheU-lobe 

 of liatnadvipia and Ariophanta ligulata. The left shell-lobe is 

 also a narrow fillet overlapping the peristome, 2 mm. broad, but 

 it has no tongue-like process on the left margin. The right 

 dorsal lobe is triangular and ample. The left dorsal lobe is in two 

 distinct parts, the anterior being the large.st, and it distinctly 

 overlaps the smaller narrower posterior lobe ; in this respect it 

 differs from typical Nihjiria solata and other species of the genus, 

 where no division of this lobe is found, and yet it is not division 

 of the same kind as is seen in Ariophanta Icevipes, &c. 



The generative organs are very similar to those of JSilgimi 

 solata. 



The central and median teeth have large cusps on both sides. 

 At the 20th tooth the cusps become very smaU, at the 23rd the 

 inner disappears, and at the 25th there is no trace of the outer ; 

 the laterals are aculeate, tlie marginals are short and bicuspid to 

 straight and blunt. The jaw has a flat convexity on the cutting- 

 edge. J 



Major diam. 44, min. 30, axis 21 mm. ; aperture 23 broad, 

 18 high. 



Bab. Hills of S.W. Ceylon ; Matelle {Layard), Kandy {Bed- 

 dome), Ambagamuwa District (Collett). 



The chestnut band below the periphery is sometimes narrow, 

 sometimes broader. The eggs are described by Collett as oval, 

 pointed at the ends, 8 mm. long and 4 wide, white, soft (uucaicified), 



