552 Records of the Indian Museum. [Vol. VIII, 



Girasia gladstonei, n. sp. 

 (Plate xlv, figs. 7— II). 



Locality. — Sadiya, Assam, 25-xi-ii, No. 5869 (5. W. Kemp). 



Shell extremely rudimentary, thin and membranaceous, the 

 apical portion only slightly thickened, very difficult to remove 

 without tearing it. It has been left in the single specimen 

 received. Colour rich ochraceous with a green tint. 



Size: major diameter 13, minor diameter g mm. 



The animal (figs. 7 — 10) much contracted in spirit, measures 

 48 mm. in length. The hinder part of the mantle rests in a deep 

 V-shaped depression. The foot is well keeled and terminates in a 

 nearly vertical narrow mucous gland (figs. 7 and 8). The peripodial 

 margin is well fringed, and from the usual two grooves above it 

 emanate many close grooves directed obliquely upwards. The 

 shell is completely hidden by the mantle, only exposed at the 

 very small oval hole situated where the right and left shell lobes 

 reach (fig. ii). From this opening a cicatrical line marks the 

 uniting of these lobes, and it extends to the respiratory orifice. 

 The sole of the foot is indistinctly divided. The dividing line of 

 the left shell lobe and left dorsal lobe is also well seen. The 

 mouth or oral aperture is beautifully displayed in this specimen 

 (fig. 10). It slightly protrudes, a semicircle of over 20 lobulate 

 organs lie above and on both sides of the jaw, while two large 

 palps with a slit between them came in below and form the 

 anterior portion of the odontophore. I name this species after 

 Mr. J. S. Gladstone who has helped me so much in the illustrating 

 of this paper. 



Genus Dihangia, nov. 



Dihangia koboensis, n. sp. 



(Plate xlv, figs. I— 6fl; pi. xlvi, figs. 4 — 46 ; pi. xlviii, 

 figs. 1—5). 



Locality. — Kobo, Assam (No. 5867) animal figured, and Sadiya 

 (No. 5874-5) dissected (S. W. Kemp). 



Shell (figs. 6, 6a) ovately spatulate, broad, very flat, smooth, 

 shiny as viewed from above, angular towards the apex; sculpture 

 striation of growth only; colour umber brown; apex white; small, 

 rounded ; whorls one, large and ample; peristome thin. 



Size: maj. diam. 12*5; alt. axis 5*5 mm. 



The shell recalls that of Girasia cacharica, G.-A., Moll. Lnd., 

 pi. lix, figs. 4a, 46, also G. (Ibycus) sikimensis, G.-A., fig. 26, but 

 in both these it is much narrower in minor diameter. When the 

 shell is removed the apical portion of the visceral sac (pi. xlviii, 

 fig. 5) shows only a very slight remnant of the first whorl, and 

 under the area which the shell covers are found the most vital 

 organs, such as the heart, hermaphrodite gland and the branchial 

 cavity. The visceral sac fills the whole of the foot up to within 



