298 



ON THE GENUS GIRASIA. 



[Apr. 20, 



List of species o/Austenia. 



Naga. 



gigas, Bs., Khasi 

 gigas, var. minor, 

 gigas, small var, Khasi. 

 solida, G.-A., Khasi. 

 minutu, G.-A., Dafla. 



cinerea, G.-A., Dafla. 

 salia, Bs., Khasi. 

 venusta, Theob. ?, Burmah. 

 resplendens, Nevill, Upper 

 Burmah. 



Still retained provisionally in Helicarion. 



verrucosum, G.-A., Dafla. 



ovatum, Hy. Bit'., Darjiling. 



bensoni, Pfr., Calcutta. 



planospira, Bs. ( — succina, 

 Reeves?), Darjiling. 



scutella, Bs., Kashmir. 



flemingianum, Pfr., Sindh. 



christiance, Theob., Anda- 

 man. 



irradians, Pfr., Ceylon. 



monticola, Bs., W. Hima- 



cassida, Ilutt. & Bs., W^. Hima- 

 laya. 

 birmanicum, Phil., Mergui. 

 heteroconcha, Hy. Blf., Darjiling. 

 membranaceum, Bs., Ceylon. 

 edgarianum, Bs., Ceylon. 

 layardi, Bs., Ceylon. 

 extraneum, Fer., Calcutta ? 

 tennentii, Temp. ?, Ceylon. 

 prcEstans, Gould?, Tenasserim. 

 auriforme, W. Blf., Nilgiri Hills. 



laya. 



EXPLANATION OF THE PLATES. 

 Plate XXIV. 

 Fig. 1 & 2. Animal of CHrasia magnifica, nat. size. Specimen in Indian 

 Museum, Calcutta. G.ap, genital aijerture, skewing the end of the 

 amatorial organ projecting from it. 



3. Aiistcnia gigca^, small var. View of right side, showing the respiratory 



and anal orifices. r.d.L, right dorsal lobe; l.d.l., left dorsal lobe; 

 r.s.l., right shell-lobe ; l.s.L, left sheU-lobe. 



4. The same. View of left side. 



5. Tlie same. Viewed from tlie back, apical portion cut off. h.d.. posi- 



tion of the hermaphrodite duct. 



6. Portion of capreolus of A. gigas, small var. </, strap-like basal portion ; 



b', base of sac, with cervicoru processes ; h", the membranous sac. 



7. Jaw of A. gigas. a, cleft in which the muscles of the upper lip are in- 



serted ; ?;, lower free edge. 



8. Shell of A. gigas, Bs., nat. size. 



y. A. gigas, var. minor, Gr.-A., nat. size. 

 10. Girasia shillongensis, G-.-A., nat. size. 



Pl.\teXXV. 

 Fig. 1. Genital organs of Austenia gigas, small 



Khasi Hills. Side view. 



^ig' 



2. The same, seen from above. 



3. Intestine, salivary gland, &c., viewed from above. 



4. Genital organs removed from the animal. 



5. Basal portion of the spermatheca. 



j.s])., point of attachment to oviduct ; a, strap-like portion of the 

 capreolus ; h.d., hermaphrodite duct ; al.gld., albumeu-ghmd ; ov., 

 oviduct ; v.d., vas deferens; B, dart-sac ; P, penis; Pc, coceum cal- 

 ciferum ; S^p., spermatheca ; r.m.p., retractor muscle of penis ; 

 OMi.gld., mucous gland; i., intestine; m., retractor muscle of head 

 and buccal mass. 



Plate XXVI. 



1. Shell and neck-lobes of Austenia gigas, var. minor, G.-A. 



2. Penis oi A. gigas, Bs., showing the position of the capreolus or sperma- 



tophore during the period of development, x 3. 2 a. Concretions from 

 calciferous gland or Kalksack. 



