UNIO. 



XXXV, 



Spi'cies 1S2. 



Umo MlCANs. Uii. ii'sid (iblungo-siihcUiplird, mIicoi,/- 

 pi-rssK, lavujatd, nitenti', soUdii, intiis ru-ico-liiiesceii/r, 

 extmfmcd, sparsim viridi radlatd, latere aiitico brevi, 

 rotunda, latere podico elongalo, angiilaio, <tiigulo ad 

 termbinm acumiiiato, margine dorsuli rcctiKsc/i/n, brevi, 

 margine laterali perubliquo. 



The shining Unio. Shell obloiig-subelliptical, sub- 

 compressed, smooth, shining, solid, sabnon-poloured 

 within, brown without, sparingly radiated with green, 

 anterior side short, round, posterior side elongated, 

 angulnted, angle acuminated at the end, dorsal mar- 

 gin rather straight, short, lateral margin very oblique. 



Le.i, Unio viii. p. 63. pi. iii. f. 207. 



Hab. Catawba River; VVheatley. Deep River Gulf; 

 Emmons. 



Species 183. (Mus. Cuming.) 



Unio pellucidus. Uu. testd subomtd, lenai, inflatd, 

 i/itus purpurea, extus leviter sulcata, Juacd-vlridescente, 

 viridi radiatd, latere aiitico brevi, rolmiih), anyudo, 

 latere postico lata, iiijiata, ad teniiinniit trnnrati), mar- 

 gine dorsali elevato, subulatu, margine n'li/ra/i ad 

 medinm paulo contracto. 



The pellucid Unio. Shell subovate, thin, inflated, 

 purple within, lightly sulcated, greeuish-browu with- 

 out, radiated with green, anterior side short, round, 

 narrow, posterior side wide, inflated, truncated at the 

 end, dorsal margin elevated, subalated, ventral mar- 

 gin a little contracted in the middle. 



Lea, Unio iv. p. 4-1. pi. ii. f. G. 



Uab. Chatahoochee River, Georgia. 

 Curiously inflated at the posterior side. 



Species 184. (Mus. Cuming.) 



o iiETERODON. Un. testa subtrapezoidea, teiiiii, sub- 

 injlatd, iiitus alba, extus viridi, concentrici leviter sul- 

 cata, latere antico brevittsculo, superne recto, aiigulato, 

 ad terminum rotunda, latere postico obtuse angulato,post 

 aiigulum bisulcato, ad terminum acuminata, margine 

 dursali reciiusculo, margine laterali perabliquo, unibo- 



nihiis tnberculalis, rardine udus dcnte cardnial, dupli- 

 call). 



The double-toothed Unio. Shell sublrapezoidcd, thin, 

 somewhat inflated, white within, green without, 

 lightly concentrically grooved, anterior side rather 

 short, straight above, angulated, rounded at the end, 

 posterior side obtusely angulated, with two grooves 

 behind the angle, acuminated at the end, dorsal mar- 

 gin rather straight, lateral margin very oblicpie, um- 

 bocs tuberculated, inside of hinge with a double car- 

 dinal tooth. 



Lea, Unio i. p. 42. pi. viii. f. 11. 



Ilab. Georgia. 



This rather wedge-shaped shell is lighter, more inflated, 



and shorter than U. niicans. The cardinal tooth in the 



/<// vahe is divided near the centre. 



Species 1S5. (Mus. Cuming.) 



Unio confertus. Uh. testd oblongd, crassd, tumidd, intus 

 carHea, extus uUvaced-nigrescenti, latere antico brevi, 

 rotunda, latere postico obscure biangulato, inter angulos 

 Irnncato, margine dorsali snbdeclivi, margine laterali 

 ohliqua, margine ventrali rectiusculo. 



The compact Unio. Shell oblong, thick, tumid, flesh- 

 coloured mthin, blackish-olive without, anterior side 

 short, round, posterior side obscurely biangulated, 

 truncated between the angles, dorsal margin slightly 

 sloping, lateral margin oblicpie, ventral margin nearly 

 straight. 



Lea, Trans. Amer. riiil. Soc. vol. v. t. Itl. f. 47. 



Ilub. South Carolina. 



A rather straight, (jblong shell, covered with a blackish 



epidermis. 



Species 186. (Mus. Cuming.) 



10 PAKVUS. Uu. testd ovali, tenui, subinflatd, iutus 

 alba, extus viridi, l(Bvigatd, latere antico brevi, rotunda, 

 medio vix contracto, latere postico oblongo, snbinjlata, 

 ad terminum acuminalo, ubscuri biangulato, umbonibus 

 subconcentrice undulatis. 



