MOLLtlSCA OK IJS^UIA, 65 



0'6 inch. This was put in a tube and dried up very well, and when 

 soaked out I was enabled to make out the generative organs to the 

 extent shown in fig. 11. The amatorial organ is present and is 

 short and thick, and the spermatheca of rather short dimensions. 

 The jaw (fig. 9) is rounded above, with a slightly concave cutting- 

 edge. The radula (figs. 10, 10 «, 10 b) was like that of B. levicida, 

 but the teeth are much larger, though serrated in the same manner, 

 the central tooth being a single straight-sided point or spike ; the 

 side teeth have six well cut serrations. The formula was 



320 . 1 . 320. 



In my description of Benson's Vitrina saJius, Vol. I. p. 152, I 

 put it into the subgenus Austenia with a ?. Mr, Theobald's obser- 

 vation, recorded by Benson, of its jumping habits, which the animal 

 now described also displayed, leads me to think that salius in ail 

 probability belongs to the genus DurgeUa^ a point I trust may some 

 day be cleared up. Some of the other and similar species figured 

 on Plate XXXV II. may also belong to it. 



Dfegella christians, Theobald. (Plate LXXIX. figs. 1-5.) 



Vitrina Christiana!, Theobald, J. A. S, B. p. 245 (1864). 



Vitrina christiame, Hanley, Conch. Ind. pi. Ixvi. figs. 7-10 (1870). 



Helicarion (sec. C) cJiristiance, Theobald, Cat. L. & Freshw. Shells 

 India, p. 24 (1876). 



Helicarion christiance, Nevill, Hand-list, p. 14 (1878). 



Durgella christiance, Godwin-Austen, A. M. N. H. p. 377 (Nov. 

 1881). 



"Shell (original description) (fig. 1): — Testa suhglobosa, tenuis, 

 polita, diaphana, nitida, supra costulate striata, infra pJanior, colore 

 succineo ; apice pallida, vix elevatiuscido ; peripheria rotiindata ; 

 apertura parum ohliqua; anfractibns 3|, lente crescentibus. Long. 13, 

 lat. 11, alt. 8 millim. 



" Habitat in insulis Andamanicis. 



" I have much pleasure in naming this shell after the lady of the 

 present Governor of the Settlement, Lieut.-Col. Tytler, as a mark 

 of esteem and pleasing remembrance of my sojourn at Port Blair 

 in his hospitable mansion. It is of the same type as V. bensoni, Pfr., 

 but is at once distinguished from all species I am acquainted with 

 by its brown colour." 



Original description, 1881 : — " Animal [PI. LXXIX, fig. 21 from 

 spirit-specimen about 1 h inch long when fully extended. Whole body 

 very dark (probably indigo-grey), with the shell-lobes conspicuously 

 pale-coloured. Apparently long, and foot narrow, with a distinct 

 central area [fig. 2 6] and lateral pallial line. The right neck- 

 lobe is small, dark-coloured, of triangular form, the left neck-lobe 

 commencing as a very narrow strip at the respiratory orifice, and 

 widening gradually, but to no great extent, towards the left side. 

 The right shell-lobe is largely developed even as contracted in the 

 spirit, and in life must extend over all the right and posterior side of 

 the shell. The left shell-lobe is given off^ from the edge of the mantle 

 on the left anterior margin, and is broadly tongue-shaped, in length 



H 2 



