UYDKOCENA. 



3 



lucente, versus spirain riibello-fu.«ca, spira nitida, eloagiito-couica, 

 sutura profunda, apice obtiisiusculo ; aiit'ractibus 4 valde couvexis, 

 ultimo ^ totius testje superaute ; apertura obliqua, ovata, superne 

 angulata, peristomate teuiii, nou coiitinuo, margiiiibus conniven- 

 tibus, dextro recto acuto, columellari reflexiuseulo. Operculo 

 tenui, corneo, pellucido, pauci-spirato, nut-leo basal i. 



Alt. 2-6o, diam. TfJo mm. 



Hah. Phie Than, Tenasserim, adhering to stones. 



"Nearly allied to Jhj<lrocetia {C'l/clostoma) saritla, nobis, 



but more slender in form." 



4. Hydroceua (Georissa) pyxis {Benson). 



Hydrncena (Georissa) /n/.ris ( Hanson), A. M. N. II. ser. '2, xvii, ISoO, 

 p. 232 {-AS Hi/cirocrna) ; Pfeiffer, .Mon. Pueuni. ii, p. IGl (as Hi/dro- 

 ccena) ; H. >fc T., C. i. pi. 117, tig. 3 (as Hydroca'ua). 



Original de.<icription : — 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 testte aequante ; apertura obliqua, semi- 

 circular!, peristomate tenui, acuto, nou continuo, margine 

 columellari expauso, reflexiuseulo. Operculo — ? 



Alt. I'-'i, diam. V'lo u)m. 



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 (Georissa) fraterna, Theobald ^- Stoliczl-a. 



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

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



Orii/inal description : — Testa cylindraceo conoidea, solidula, 

 pallida, iraperforata, regione umbilicali paulo impressa ; anfrac- 

 tibus 3;j, convexis, supra modice subtruncatis, sutura per-prcfuuda 

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

 f«upera a sutura remotiuscula : apice valde raatnillato ; ultimo 

 anfractu spira breviore, basi convexiusculo, spiraliter striato ; 

 apertura fere semicirculari, labro simplici, autice modice recedente, 

 margine subobtuso instructo, labio recto, incrassato ; operculo 

 testaceo, tenui, subdiaphano, paucispirato. 



Alt. 1"4, diam. maj. '1)5 mm. 



J fab. Atarau Jiiver Valley, near Moulmein. 



" Allied to G. 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 maramillate, and the entire form of the shell mora 

 slender and cylindrical." 



jj2 



