4 HYDROCENID^. 



6. Hydrocena (Georissa) frustillum (Benson). 



Hydrocena (Georissa) frmtillum (Benson), A. M. N. II. ser. 3, vi, 

 1860, p. 193 (as Hydrocena} ; Pfeiffer, Mon. Pneum. iii, p. 251; 

 H. & T., C. I. pi. 117, fig. 5 (as Hydrocana). 



Original description : Testa iraperforata, ovato-oblonga, solidi- 

 uscula, spiraliter confertissime tenuisulcata, succinea?; spira 

 subpyramidata, apice obtusiusculo, sutura impressa; anfractibus 5, 

 convexis, ultimo f testae subaequante ; apertura obliqua, truncato- 

 ovata, superne necnon ad latus sinistrurn angulata, peristomate 

 tenui, non continue, pariete calloso. Operc. ? 



Alt. 2'5, diam. 1*75 inm. 



Hob. Ava. 



Differing from G. illex (Benson), " in the absence of the very 

 elongate slender spire of that species, in the want of an umbilicus, 

 and in the form of the aperture, which presents internally an 

 angle at the junction of the coluraellar lip." 



7. Hydrocena (Georissa) rawesiana (Benson}. 



Hydrocena (Georissa) rawesiana (Benson), A. M. N.H. ser. 3, vi, 

 J860, p. 193 (as Hydrocena) ; Pfeiffer, Mon. Pneuin. iii, p. 252; 

 Theobald & Stoliczka, J. A. S. B. xli, 1872, pt. 2, p. 332 ; II. & T., 

 C. I. pi. 117, fig. 6 (as Hydroccena). 



Original description: Testa imperforata, subgloboso-conica, 

 solida, confertim spiraliter striata, luteo-albida; spira conica, apice 

 obtuso, sutura profundiuscula ; anfractibus 4, valde convexis, 

 ultimo spiram subaequante ; apertura vix obliqua, semicircular!, 

 superne et ad latus sinistrum angulata, peristonmte tenui, margine 

 parietali calloso, intus recto, stricto ; loco umbilicali subfoveato. 

 Operc. ? 



Alt. 2, diam. 1-5 mm. 



ffab. Near Moulmein in the J?arm Caves. 



" The shell is more globose than that of H. pyxis, Benson, and 

 the sculpture is altogether different. In the formation of the 

 aperture there is an approach to that of H. frustillum, but it 

 exhibits a straight knife-like edge at the internal parietal 

 margin." 



8. Hydrocena (Georissa) blanfordiana, Stoliczka. 



Hydrocena (Georissa) blanfordiana, Stoliczka, J.A.S. B. xl, 1871, 

 pt. 2, pp. 157-158, pi. 6, fig. 6 ; xli, 1873, pt. 2, p. 332 ; H. & T., 

 0. 1. pi. cxvii, fig. 2 (as Hydroc&nu). 



Original description: Testa globoso conoidea, imperforata, 

 moderate solidula, Juteola, apice rubescente, mammillato lvissinio; 

 anfractibus 3|, convexiusculis, trans versaliter striis increment! 

 urinutis tectis, sublsevigatis ; ultimo ad peripheriam rotundato, in 

 altitudine spiram subaaquante ; apertura late semilunari ; labro, 



