﻿C Y R E N A. 



Plate VI. 



Species 17. (Mus. Brit.) 



Cyrena Childreni. Cijr. testa suhroiumld, com^i-r-isii, 

 hevigatd, fiisco-viridescenti, intm cameo violaceo- 

 que nebulaid; latere antico brevi, declicr, liris 

 panels hrevilnis rugatd ; latere postico suhinflato, 

 rotimdatim angulato ; viargine dorsali recthhculo, 

 margiiie ventrali convexo, margine postico oblique 

 suhqwadraio. 



Children's Cyeena. Shell rather rounded, com- 

 pressed, smooth, greenish brown ; within clouded 

 with flesh tint and violet ; anterior side short, 

 sloped, wrinkled witli few short ridges ; posterior 

 side rather inflated, roundly angular; dorsal 

 margin rather straight, ventral margin convex, 

 posterior margin obliquely subquadi-ate. 



Gray. jMS. Mus. Brit. 



Bah. Philippines. 



Species 18. (Mus. Brit.) 



Gyrena humerosa. Cyr. festd ovato-subtrigond, c(L<!ta- 

 ned, latere antico brevi, declivi, sithacuminato, 

 conspicue lirato; umbonibus depressis, obtusis ; 

 latere postico obtuse biangulato, laivigato, versus 

 angidum posticum tumido, gihboso, margine dorsali 

 elevato, subalato. 



The shouldered Cyrena. Shell ovate-subtrigonal, 

 chestnut, anterior side short, sloped, rather 

 acuminated, conspicuously ridged ; umboes de- 

 pressed, obtuse ; posterior side with two obtuse 

 angles, smooth, very tumid and gibbous, dorsal 

 margin raised, somewhat ^Wngod. 



Deshayes. Proc. Zool. Soc. lb.54, p. 1-1. 



Hah. ? 



Although a little resembling Ci/r. trlqid'fni, Desh., 



this species is not so elevated at the dorsal mai-gin, 



nor so directly sloped in front. 



Species 19. (Mus. Brit.) 

 CvnE.NA Jatensis. Cyr. testa rotunda, altd, solidd, 

 turaidd, castaned, versus marginem viridescenti ; 

 latere tintiro brevissimo, ad marginem area depressd 

 fiiiuatn, sulcis brevibns rugato ; umbonibus rotun- 

 ilis, jirnmiveidihus ; latere postico inflaio, rotundo, 

 iiifiignic dcrsiili elevato ; ligamento nuigno. 



Jay's Cyrena. Shell round, liigh, .solid, tumid, chest- 

 nut, becoming greenish towards the margin ; 

 anterior side very short, sinuated at the margin 

 by a depressed area, wrinkled with short grooves; 

 umboes rounded, prominent ; posterior side in- 

 flated, round, dorsal margin raised ; ligament 

 large. 



Lea. Trans. Am. Ph. Soc. Vol. ',. PL XVII, f. ry^. 



H,tb. Waigiori. 



Species 20. (Mus. Brit.) 



Cyrena gracilis. Cyr. testd suhrotuudd, complmatd, 

 funwso-stramined, intm carneolo purpureoque 

 suffiisd; latere antico brevissimo, area depressd 



a.i.jn.fu, s„j,n 

 a.,g.h,t., r-t 

 ba.n,gnt.,; ,„ 



dnr^ui; 



,l,',;iri 



,li>^i„„li- 

 """■'jiiie 



postico oblique subtrunciito. 



The slender Cyeena. Shell rather round, flat, 

 smoky straw, within sufi'used with flesh and 

 purple ; anterior side very short, with a narrow 

 depressed area, sloped above; posterior side 

 obliquely angular, wrinkled behind the angle 

 with diverging ridges ; dorsal margm nearly 

 straight, posterior margin obliquely ti'uncated. 



Prime. Proc. Zool. Soc. iHtjO, p. 319. 



Hab. ? 



Species 21. (Mus. Brit.) 



Cyrena corbuloides. Cyr. testd oblique subtrigond, 

 SHbcornpressd, altd, compJnnatd; vivide viridi- 

 fmrr^,:r„ti : ei'nh-n,u,l: loalulaflm siriatd i„<l:,fd; 

 l„lrrr ,n,'irn lu-rri.si ,u... ni.ir.jiin, 1,,/rrah' raid,) 

 derlicl, nuihniuhiL, d.v.itia; l„frr,- pa.tn:., nhsrarc 

 trigono, inargine ventrali rectitlsculo. 



The corbula-shaped Cykena. Shell obliquely subtri- 

 gonal, subcompressed, high, flat, bright brownish 

 green, covered with a wavily striated epidermis, 

 anterior side very short, lateral margin much 

 sloped downwards, umboes i-aised ; posterior side 

 obscurely trigonal, venti-al margin rather straight. 



Deshayes. Proc. Zool. Soc. 1854, p. 14. 



Hah. Louisiade Ai-chipelago. 



