HYDROCENA. 3 



lucente, versus spiram rubello-fusca, spira nitida, elongato-conica, 

 sutura prof uiida, apice obtusiusculo ; anfractibus 4 valde convexis, 

 ultimo -^ totius testae superante ; apertura obliqua, ovata, superne 

 angulata, peristomate tenui, nori continue, marghribus conniven- 

 tibus, dextro recto acuto, columellari reflexiusculo. Operculo 

 tenui, corneo, pellucido, pauci-spirato, nuuleo basali. 



Alt. 2'65, diam. 1*65 mm. 



Hab. Phie Than, Tenasserim, adhering to stones. 



"Nearly allied to Hydrocena (Cyclostoma') saritta, nobis, 



but more slender in form." 



4. Hydrocena (Georissa) pyxis (Benson). 



Hydrocena (Georissa) pyxis (Benson), A. M. N. II. ser. 2, xvii, 1850, 

 p. 232 (as Hydrocena) ; Pfeiffer, Mon. Pneum. ii, p. 161 (asHydro- 

 ceena) ; H. & T., C. I. pi. 117, tig. 3 (as Hydroccena). 



Original description : Testa obtecte perforata, ovato-conica, 

 spiraliter sulcata, succinea, translucente, spiram versus rubente ; 

 spira conica, sutura profunda, apice obtuso ; anfractibus 4 con- 

 vexis, ultimo f totius testae aequatite; apertura obliqua, semi- 

 circulari, peristomate tenui, acuto, non continuo, margine 

 columellari expanse, reflexiusculo. Operculo ? 



Alt. l*o, diam. 1*25 mm. 



Hab. Thyet-Mio. 



" H. pyxis, although smaller than H. illex, is more coarsely 

 sulcate, and the furrows on the lower whorl are more distant near 

 the suture than below." 



5. Hydrocena (G-eorissa) fraterna, Theobald $ Stoliczka. 



Hydrocena ( Georissa} fraterna, Theobald & Stoliczka, J. A. S. B. 

 xli, 1873, pt. 2, p. 332, pi. 11, figs. 5, 6. 



Original description : Testa cylindraceo conoidea, solidula, 

 pallida, iraperforata, regione umbilicali paulo impressa ; anfrac- 

 tibus 3|, convexis, supra modice subtruncatis, sutura per-prcfundu, 

 junctis, spiraliter crasse liratis, liris in anfractu penultimo quiuque, 

 supera a sutura remotiuscula : apice valde mamillato ; ultimo 

 anfractu spira breviore, basi convexiusculo, spiraliter striato ; 

 apertura fere semicirculari, labro simplici, antice modice recedente, 

 margiue subobtuso instructo, labio recto, incrassato ; operculo 

 testaceo, tenui, subdiaphano, paucispirato. 



Alt. 1'4, diam. maj. '9o mm. 



Hab. Ataran Eiver Valley, near Moulmein. 



" Allied to O. pyxis in having the uppermost spiral ridge on the 

 whorls somewhat remote from the suture, but the ridges them- 

 selves are stronger, the whorls somewhat less numerous, the apex 

 very distinctly mammillate, and the entire form of the shell more 

 slender and cylindrical," 



