U N I 



Plate XV. 



Species 61. (Mus. Cuming.) 



UxiO DEVIATUS. Uil. ledii oblongo-qiiadratfi, an/ ice ab- 

 breviato-atteiii'.aid, poslice ampliter expansd, augidarl- 

 ler late truncatd; lulescente-oUvaced, viridi copiose ra- 

 diatim Ibieatd. 

 The deviating LTnio. Shell oblong-square, anteriorly 

 shortly attenuated, posteriorly largely expanded, an- 

 gularly broadly truncated ; yellowish-olive, copiously 

 radiately lineated with green. 

 Anthony, MS. in Mus. Cuming. 

 Hab. North America. 



Truncately fan-shajjed on the posterior side, rather at- 

 tenuated anteriorly. 



Species 62. (Mus. Cuming.) 



Unio Haystanus. Uii. testd ovuto-f/luhom, gibbomsdmd, 

 poslice radiatim Uratd et lineari-snlcatd, liris versus 

 warginem serratis, antice Imvigatd; lutescente-oVwacea. 



Hays' Unio. Shell ovately globose, very gibbous, pos- 

 teriorly radiately ridged and linearly grooved, ridges 

 serrated towards the margin, anteriorly smooth; yel- 

 lowish-olive. 



Lea, Trans. Araer. Phil. Soc. 1832. Obs. vol. i. p. 147. 

 pi. 3. f. 7. 



Ilab. Cumberland Piiver, North America. 



The posterior area is often defined by a prominent ridge- 

 like swelling radiating to the ventral margin. 



Species <j?>. (Mus. Cuming.) 



Unio ridibundus. Tin. testa suboblongo-quadrald, gib- 

 bositisctdd, antice sublatd, ventricosd, poslice ftt'xmso- 

 tnmcatd, obscure lineari-sulcatd, liris versus marginem 

 serratis ; lutescente-oUvactd, viridi Uneari-radiatd. 



The labghing Unio. Shell somewhat oblong-square, 

 rather gibbous, anteriorly rather broad and ventricose, 

 posteriorly flexuously truncated, obscurely linearly 

 grooved, ridges serrated towards the margin ; yel- 

 lowish-olive, linearly rayed with green. 



Say, Amer. Couch. 



Hab. North America. 



This closely resembles U. suh-atus, of which species Mr. 



Lea believes it to be the female. It differs malcriallv in 

 respect of form, being more of an oblong square. 



Species 64. (Mus. Cuming.) 

 Unio peesonatus. Uu. testd subqiiadrato-orbiculari, 



perobliqnd, gibbosd, poslice radiatim flexuoso-imdotd, 



lineari-snlcatd, nmbonibm prominenti/jiis ,• sordide 



fasco-olimced. 

 The masked Unio. Shell somewhat squarely orbicular, 



very oblique, gibbous, posteriorly radiately flexuously 



waved, linearly grooved, umboes prominent ; dull 



fuscous olive. 

 Say, Conrad, Monog. pi. 2-i. 



Unio capiUaris, Lea. 

 Hah. Ohio lliver, North America. 



A round gibbose shell with prominent umboes radiately 

 linearly grooved on the posterior side. 



Species 65. (Mus. Cuming.) 

 Unio Edgarianus. Un. testa coinpressH cnneiformi, 

 medio contractu, poslice declivi-angidatd ; lulescentv- 

 olivaceu, nigricante-viridi copiose radiatd. 

 Edgar's Unio. Shell compressly wedge-shaped, con- 

 tracted in the middle, posteriorly slopingly angled ; 

 yellowish-olive, copiously rayed with blackish-green. 

 Lea, Trans. Amer. Phil. Soc. Second Series, vol. viii. 



Obs. vol. iii.p. 52. pi. 15. f. 30. 

 Hab. Tennessee River, North America. 



A very compressed wedge-shaped shell, copiously ra- 

 diately pencilled with very dark green. 



Species 66. (Mus. Cuming.) 



Unio Stewardsonii. Un. testd oblique qnadrald, gib- 

 boso-conve.ru, poslice lui/iido-bipartitd, untice brecis- 

 siind ; ltsvigatu,fnscescenle-olivaceu. 



Stewardson's Unio. Shell obliquely scpiare, gib- 

 bonsly convex, posteriorly tumidly bipartite, ante- 

 riorly very short ; sn\ooth, fuscous-olive. 



Lea, Trans. Amer. Phil. Soc. Second Series, vol. x. Obs 

 vol. v. p. 34. pi. 23. f. 36. 



Hab. Cluitauooga River, North America. 



November, 1864. 



