U N 10 



Spec 



36. (Mub. Cuming.) 

 >. Uii. testa triyono-ovald, subtequl- 



Unio sesiigr\> 



lateralis concept rice rude plicatd, imdiquc dense verrii- 

 mso-i/raiiald, grains ad latiis atiticum evaiiidis ; sor- 

 ilnli' otieaced, intiis cupreo-pitrpured . 



TiiK n.iLF-Git.MNED Unio. Shell triangularly ovate, 

 nearly equilateral, concentrically rudely plicated, 

 closely wart-grained throughout, grains fading away 

 on the anterior side ; dull olive, interior coppery- 

 purple. 



Philippi, Mag. de Zool. 18-i3, p. US. 



Hab. Mexico. 



This, and the species given at Fig. 37 an 

 a characteristic granulated type of the ge 

 Mexico. 



39, represent 

 Lis peculiar to 



Species 37. (Mus. Cuming.) 



Unio pliciferus. Un. testa subelonyato-ovatd, veiitri- 

 cosissiiiid, poslice decUvi-acitminatd, copiose verrucoso- 

 yranatd, (/rams ad nream posticam in plicis radianti- 

 hus ; olivaceo-nigrd, itUus cupreo-purpured. 



The plaited Unio. Shell somewhat elongately ovate, 

 very ventricose, posteriorly slopingly acuminated, 

 copiously wart-grained, grains on the posterior area 

 in radiating folds; olive-black, interior coppery- 

 purple. 



Tea, Trans. Anier. Pliil. See. 1S36; Obs. vol. ii. p. 61. 

 pi. 17. f 53. 



Ilab. Jlexieo. 



Characterized by the same granular sculpture as the 

 preceding species, the gnuns on the posterior area ran- 

 ging in radiating folds ; the shell is of peculiarly ventricose 

 growth. 



Species 3S. (Mus. Cuming.) 



Unio Dokfeiiillianus. I'n. testa subqundrnlo-rotHndiU 

 gibbosd, postici fexiwso-angnlatd, tr/ii/catd, sjjaraim 

 tiibercidatd, tii/je/ridis interdiiM vi.r ukIUs ; intense 

 olivaced. 

 DoRFEniLLE's Unio. Shell somcwhat squarely rouiuled, 

 gibbous, posteriorly ilexuotisly angled, and truncated, 

 sparingly tidjercled, sometimes scarcely any ; dark 

 olive. 

 Lea, Trans. x\mer. Phii. Soc. 1836 ; Obs. vol. ii. p. 73. 



pi. 17. f. 54. 

 Ifab. Ohio River, North America. 



A moderately t\d)ercled shell, rudely flexuously trun- 

 cated on the posterior side. 



Species 39. (Mus. Cuming.) 



Unio corium. Un. iestd subqitadraio-oblongd, depressias- 

 culd, postice Jkviwse obtuse angulald, Iruncatd, con- 

 centrice subrude plicatd, circa umbones dense verrucoso- 

 granatd ; sordide olivaced, intus palUde rosaceo-pur- 

 purascente. 

 The shagreen Unio. Shell somewhat squarely oblong, 

 rather depressed, posteriorly flexuously obtusely 

 angled and truncated, concentrically rather rudely 

 plicated, around the umboes closely wart-grained ; 

 dull olive, interior pale rose-purple. 

 Hab. Chiapa, Mexico. 



The form of this shell is too widely distinct from that 

 which we have figured as Mr. Lea's U. pliciferus, to allow 

 of it Ijcing regarded as the same species, but it is impos- 

 sible to foresee whether they might not be connected by 

 an extended series of specimens. 



August, 1864. 



