U N I 



Species 337. (Mus. Sowerby.) 

 Unio subangulatus. Uu. ovalo-iubciiiicifurmi, lenni, 

 Imviyalu, stramined, podice fasciis at. Imeis viridifji/n 

 radiatn, inlus pallidh Halwoned ; latere postico ob- 

 tusi angulalo, maryimi donali eli'Mto, snbalnio, um- 

 bonibi(>i acutls, litvibiis ; latere aiitico bred, aiigustato, 

 rotunda, dentibus aiiticis parvis, poxticis temiibiis, lii- 

 minatk. 

 The subangular Unio. Shell ovrtte-subcuiieifonn, tliiii, 

 smooth, straw-coloured, rayed posteriorly with green 

 bands and lines, pale salmon within ; posterior side 

 obtusely angular, dorsal margin elevated, subalate, 

 umboes acute, smooth; anterior side short, narrow, 

 round, anterior teeth small, posterior thin, laminar. 

 Lea, Obs. on Unio, vol. iii. p. 47. pi. 13. f. 23. 



trfcir/ntii. iiitiia siibaiirauti, 



i/eti,(/eiitibiis 



par 



Hub. Chattahooe 



Cohmibn^ Georgi; 



Species 338. (Mns. llauley.) 



Unio spatulatus. Uu. testa oblongo-subovatd, com- 

 preand, liBcigatd, Jlavido-ritfenceuti, fasciis et liueis 

 oiridihus medio rudiatd, intils albidd ; latere postico 

 producto, prope margiiiem dorsatem oblique depressn, 

 margiiie dursali arcuato, prope lerminum excavato, ter- 

 iiiiiw uciiiiiiiiatiiii rolundo, margine veidrali ad ter- 

 iiiiiiniH sarsiim acclivi, medio rectiusculo, vmbonibus 

 tuberculis widatia armatis ; latere antico rotunda, 

 margine dorsali declim. 



The spatolate Unio. Shell oblong-subovate, com- 

 pressed, smooth, reddish-yellow, rayed in the middle 

 with green bands and lines, white within ; posterior 

 side produced, obliquely depressed near the dorsal 

 margin, dorsal margin arched, e.x.cavated near the 

 end, end aeuminately rounded, ventral margin sloped 

 upwards at the end, middle rather straight, umboes 

 armed with waved tubercles; anterior side round, 

 dorsal margin sloped. 



Lea, 01)s. on Unio, vol. iv. p. 51. t. f. 33. 



Hub. Ruck river, Wisconsin. 



Species 339. (Mus. Sowerby.) 

 iEGLECTUS. JJn. testa tenui subinflald, ovato-sub- 

 ■teiformi, luteold, antice concent rice rugatd, postice 



lateral ibnx Irnuibiis ; latere postico lata, obtusi: angu- 

 lalo, tuinida, snbiiiHidratii ; latere antico angusto, sab- 

 depresso, margiue dorsali ilcclici, tenninu subai-uini- 

 uato. 



The neglected Unio. Siiell thin, subintlated, ovate- 

 siibcuneiforni, didl yellowish, couceutrically wrinkled 

 in front, smooth behind, slightly oiange and bluish 

 within, teeth small, the lateral ones thin; posterior 

 side wide, obtusely angular, tumid, subquadrate ; an- 

 terior side narrow, subdepressed, dorsal margin sloped, 

 end subacnminated. 



Lea, Obs. on Unio, vol. iv. p. 38. pi. 43. f. 10. 



Uab. North Alabama. 



Species 330. (.Mus. Taylor.) 

 Unio tortuosus. Uu. tesld coiupressd, laid, solidd, tra- 

 pfzoided, slriis et rugis sublavigatis depressd, iutits 

 purpured, epidermide fasco-subviridi, obscure radiatd, 

 valralis ad iiiaryinem ventralei/i tortuis ; latere postico 

 oblique angulalo, aiigulo tumido, obtuso, a red post a n- 

 (jnlari costis duabus suhevanidis radiatd, margiue dor- 

 sali rectiusculo, laterali obliquo, tenuino basali sub- 

 acuminato, mnbonibus parvis, margine veutrali medio 

 subcantracto ; latere antico superne oblique cunealo. 

 The tortuous Unio. Shell compressed, broad, solid, 

 trapezoidal, impressed with rather smooth strire and 

 wrinkles, inside purple, epidermis greenish-brown, 

 obscurely rayed, valves tortuous at the ventral margin ; 

 posterior side obliquely angular, angle tumid, obtuse, 

 postangular area rayed with two almost obsolete ribs, 

 dorsal margin rather straight, lateral margin oblique, 

 basal termination subacuniinated, umboes small, ven- 

 tral margin slightly contracted in the middle ; ante- 

 rior side obliquely cuneate above. 

 Sowerby. 

 Hab. Maryland. 



The fine shell here described differs from T. purpureu\ 

 (U. complauatus. Say) in its greater breadth and its tra- 

 pezoidal form. The unsymnietrical curve in the ventral 

 margin may possibly be accidental. 



January, 1SG8'. 



