U N I . 



Plate XXWllI. 



Species 20(1, (Mus. Cuming.) 



Unio Novi-Eboraci. Uu. testa ovuli, cni,ij>rr.sx,i. hilii-s 

 alba, extusplamdatu, luted, virii/i in/rrni/i/m/ r,ii/iiifn\ 

 latere antico brevi, rotmidu, latere iin.s/icn i-lnrnjatn, mili- 

 atteniiato, obscure biangulato, ad tenn'uii:i,i trintcato, 

 area postaiigidari aiigustii, declivi, niargnie eeiitrali 

 vix medio contracto. 



The New York Unio. Shell oval, compressed, white 

 within, flattened, yellow without, with intemiplcd 

 green rays, anterior side short, round, posterior side 

 elongated, ratlier narrowed, obscurely biangulated, 

 truncated at the end, post - angular area narrow, 

 sloping, ventral margin very slightly contracted in 

 the middle. 



Lea, Unioii. p. 104. pi. xxiv. f. 114. 



Hab. Oak Orchard Creek, Orleans County, New York ; 

 .1. C. Jay. 

 This shell has an oblong, flattened surface, beautifully 



ornamented with interrupted green rays. Umboes inidated. 



Species 307. (Mus. Cuming.) 



Ukio Murchisonianus. Uh. iesld ovali-oblongd, s/dj- 

 iiijlatd, iidiis alba, exlus obscure otlnaced, ad uiuhonnnt 

 regionem vhtiqiie et iindidntiui ragiitil, ruij'ia medio et 

 iufra ecaiiidi.K, jmflcr ohiiqii? Inhereithitd, latere anlico 

 bred, rotiiudo, prope iiudiiniea sidiaiigidalii, latere por- 

 tico oblongo, acioniiiato, angulato, po.it aiigahnu ob- 

 scure bicostato. 



Murchison's Unio. Shell oval-oblong, rather inflated, 

 white within, dull-olive without, at the region of the 

 nmboes olilifpiely and undulately wrinkled, wrinkles 

 evani'sciiit in llic iniiMlc and beneath, posteriorly 

 obliipiely tnlioiculatrd, auleiior side short, round, 

 with a slight angle near the niiiliocs, posterior side 

 oblong, acuminated, anguhitcd, liL-hiiul the angle ob- 

 sciu'ely double-ribbed. 



Lea, Trans. Anier. I'hil. Soe. vol. v. t. 3. f. (3. 



Hab. China. 



The wrinkles, very beautifully arranged, which cover a 

 large portion of the surface at and near the tunboes, be- 

 come faint towards the centre, and on the lower part of 

 the shell. 



Species 208. (Mus. Cuming.) 



Unio exiguus. Un. testa obloiigd. obHijnd,a)igitsld,tniin, 

 ■Habcompressd, i>itu.i creraleo-i ndescodi , e.vtas Irpvigatd, 

 antice lated, postice viridi, nigro iddiqiie radiatd, latere 

 aidico brevissimo, rotunda, latere po.itico eloiigato, ad 

 lerannum subtruncato, viargine dorsali arcaato. mar- 

 giiie venlrali rectiiiscalo. 



The narrow Unio. Shell oblong, oblique, narrow, thin, 

 subcorapressed, blue-iridescent within, smooth with- 

 out, yellovv in front, green behind, obliquely rayed 

 with black, anterior side very short, round, posterior 

 side elongated, subtruncated at the end, dorsal mar- 

 gin arched, ventral margin rather straight. 



Lea, Unio iii. p. 29. pi. vii. f. ]. 



Hab. Chatahochee lliver, Georgia. 



A peculiarly-narrow, thin shell, light-coloured in front, 



dark at the back, and very obliquely rayed. 



Species 209. (Mus. Cuming.) 

 Unio perovalis. Uit. lestd ovali, crassd, inflatd, iidus 

 alljii, e.rtiis lerder snlcatd, olimceo-lidesceide, liueli 

 piiuetatisi etfasciis iaterritptis virid/b/is radiatd, latere 

 aidico bred, rotnndo, medio amplo, latere postico ob- 

 longo, sabacmninato, obscure biaiigulato. 

 The very oval Unio. Shell oval, thick, inflated, white 

 within, lightly sulcated, yellowish-olive without, rayed 

 with spotted lines and interrupted green bands, an- 

 terior side short, round, middle full, posterior side 

 oblong, rather acuminated, obscurely biangidated. 

 Conrad, New Freshwater Shells, p. 43. t. i. f. 2. 

 Hab. Biver Alabama. 



There is a peculiar punctured and interrupted appear- 

 ance in the bands and lines which ornament this very oval 

 sheU. 



Species 210. (Mus. Cuming.) 

 Unio TroOSTENSIS. t'li. testa bredter ovali, tenui, in/hdd, 

 iidns albd, ci-ta.s olicarrd. lalrrc nidico brcnnsculo, an- 

 gusto, rotuuilu, „irdin a„i/,/,sini,n, lulerc pnslivo, lal'ius- 

 culo, obtuse Iruuratn. uiargiue diirsuli rrrfu. po.Htice 

 elevato, margiue veutrali rotuuJo, mabouibus iujtalis, 

 tuberculatis. 



