U N 10. 



Platk XXX VJ. 



Species 1S9. (Mas. Cuining.) 



I Mil Aci'Tlssnii s. I'll, /ci/ii ptin-ii, chufjulii, compn'sisu , 

 IcHiii. iiiliis fii/esct'iih'. /'.liiis siidvirii/i, latei'e aiitico 

 brcri, mtiiiiihi, iiikjusI,!, hiicn- poslico eloiKjnto, ohlique 

 iiiKjiilato, anh: et pod (iiujidiim niyin diecryeiililjKS 

 scii/pto, teniriiie acido. 



The veky shakp Unio. Sbell elonj;ate, small, com- 

 pressed, thin, yellowish witliiu, rather green without, 

 anterior side short, round, narrow, posterior side long, 

 oliliqiiely angiilated, before and behind the angle 

 sculptured with ili\cr^iug wrinkles, cud acute. 



l.KA, linui. p. ^y.). pi. X. f. 18. 



llab. Alabama River. 



The peculiar characteristic of this little shell consists in 



the divergent wrinkles, reaching to the uuirgiu on both 



sides of the posterior angle. 



Suitably named frc 

 LUid colour. 



its resemblanct 



Species 190. 



Un'IO olans. Uii. testa ovatd, cra-ssd, tiimidd,pnrvd, lulus 

 purpurea, exlus laevigata, obscure olhacea, latere aiitico 

 brevl, rolundo, latere postico longiusculo, obscure biun- 

 gulato, inter angulos truncalo, margiue dorsali subile- 

 clivi, margiue laterali obliquo, iimbonibus ati/plis. 



The acorn Unio. Shell ovate, thick, tumid, small, 

 purple within, smooth, obscurely-olive without, an- 

 terior side short, round, posterior side rather long, 

 obscurely biangulated, truncated hetween the angles, 

 dorsal margin sliglitly sloping, lateral margin ob- 

 lique, umboes full. 



Le.i., Unio i. p. 92. \)\. viii. f. 12. 



Hub. River Oliio. 



ipe 



Species 191. (Mus. Cuming.) 

 Unio Zeigleuianus. Uu. testa pan-d, teuuissimd, jtel- 

 liicidd, ovali, siibcompressd, iiitus albesceute, extus Ice- 

 vigatd, luted, Uiiels viridibus poslice radiatd, latere aii- 

 tico bred, rotuiido, latere postico oblongo, latiiisculo, 

 termine rotuudu, margiue laU-rali supra obUquo. 



lell small, very thin, pellucid, oval, 



rather compressed, wlnlish witlun. smooth, yellow, 

 radiated with green lines without, anterior side short. 

 round, posterior side oblong, rather broad, end 

 rounded, lateral margin oblique above. 



Lea, Uiiio ii. p. 32. pi. x. f. 0. 



Hab. Cumbrrhmd Eiver, Tennessee. 



Species 193. (Mus. Cuming.) 



Unio Hildrethianus. Uii. testd eloiiguld,subcijlindricd, 

 teuid, intus iridesceuti, cvtits obscure olicaced, latere 

 antico brevi, rotiindo, latere postico i-loiignfn, siibtritii- 

 cato, margiiiibus dorsali el ceutrulL nrtis, niiihoiiUius 

 uiidulaiim rugosis. 



Hil.liitETH's Unio. Shell elongated, subcyliudrieal, thin, 

 iridescent witliin, obscurely-olive without, anterior 

 side short, round, posterior side lengthened, subtruu- 

 eate, dorsal and ventral margins straight, umboes un- 

 dulately wrinkled. 



Lea, Trans. Amer. Pliil. vol. v. t. 3. f. s. 



Hab. Ohio. 



This is a light shell of remarkably cylinilrical form. 



Species 193. (Mus. Cuming.) 



Unio tortivus. Uu. testd oblougd, coiiipressd, angustd, 

 tenia, intus caruled et earned, extus viridi-nigresceuti, 

 obscure radiatd, latere antico brevi, rotundo, latere 

 postico elougato, kitiusrido, obscure biaiigidato, margiue 

 dorsali elevato, margiue laterali perobliquo. termine 

 truiicato. 



The pressed Unio. Shell oblong, compressed, narrow, 

 thin, bluish and flesh-coloured within, blackish-green, 

 obscurely rayed without, anterior side short, round, 

 posterior side elevated, lateral margin very ol)Iii|iir, 

 truncated at the cud. 



Lea, Unio iii. p. 43.pl. xii. f. 17. 



Ihb. Chattahoochee River, Georgia. 



Zeiglek 



\h 



■s 19-1. (Mus. Cum 

 Ui. trsUi augusl.l. 



Mai 



