U N 



Species 54. (Mus. Ciiiiiiiig.) 

 Unio Rangianus. Vn. ti'std siihohlomjo-ovnld, pustice 



llcxuoso-prodiwld, obsolete radiatim tnhercidald ; tides- 



i-ente-oUvitced, viridi linean-radiatd. 

 Rang's Unio. Shell rather obloiig-ovnte, posteriorly 



flexiiously produced, obsoletely radiatcly tubercled ; 



yellowish-olive, linearly rayed with grecii/ 

 Lea, Trans. .Vincr. Phil. Soc. 1S37, Ohs. vol. ii. p. 1)5. pi. 



IS. f. 56. 

 //,,A. Ohio Kiv. r, North Aincrii-:i. 



10. 



XIV. 



Lea, Trans. Amcr. I'liil. Soc. ISSH. Olis. vol. i. p. MCk 

 pi. 17. 1'. 4k 

 Unio nexus, Say. 

 Ilab. Tennessee River, North Anicricn. 



A peculiarly gibbous species, in which the posterior 

 angle bulges out on either side, as in the typical form of 

 Hi/ssoarca. 



\('i 



ike r 



'iMc 



with the tubeirh' 



Species 55. (Mus. Cuming.) 

 L'nio PENITI'S. f'n. testa snt)trii)Ono-oblongd, yibbosis- 



shim, postici Jlej-iioso-tumidd et radiatim incisd, delude 



lute truncatd ; lidescente-olivaced. 

 The tailed Unio. Shell somewhat triangularly oblong, 



very gibbous, posteriorly flexuously swollen and 



olive. 

 CoNiiAD, Freslnvater Shells, p. 'i'-^. pi. ">. f. 1 

 Ilab. Alabama, North America. 



Distinguished by a produced swelling of tlie posterior 

 ;ni"le. \vlii<'h is radiatelv incised. 



Species 5G. (Mus. Cuming.) 



Unio INTEURUPTI'S. Un. testa arcntito-securif orm i, postice 

 lamido-aiigulatd, deinde declivi-truncald, medio sidi- 

 compressd, ad aiujulmn radiatim crisputo-sidcatd ; 

 tiUescente-oHvaced, viridi interrnple lineari-radiatd. 



The interrupted Unio. Shell arcuately wedge-shaped, 

 posteriorly tumidly angled, then slopingly truncated, 

 rather compresseil in tlie middle, railialely erLspately 

 grooved at the angle ; yello« ish-nlive, interruptedly 

 linearly rayed with green. 



Rafinesque, Moil. C^ocj. de la riv. Ohio, Ann. Gen. Sc. 

 I'hys. Brux. 1S2U, vol. v. p. 2S7. 

 I:iiiu breridi;,s. Lea. 



Ilul,. Ohio Uivei-. North America. 



ipresseit sliell, arena 

 tlie angle of which is 



curved do 

 .dIV swolle 



^pecles 



(:\Ius. Ci 



Unio Auc.efokmis. Un. testa oblomjo-eijhildforiiii, ijih- 



tjosissimd, postice tiimido-anijuUild, deiiide tatissime 



truncatd ; sordid!; otivaced. 

 The Arca-shaped Unio. Shell oblong-boat-sluiped, 



very gibbous, posteriorly tumidly angled, then very 



broadly truncated ; dark olive. 



Species 58. (Mus. Cuming.) 

 Unio Sowerbyanvs. Uii. testa triffono-cordatd, pos/ici 

 fexiwso-iinpressd et radiatim sulcata, aiitice laviijald , 

 intense olivaced. 

 Sowekby's Unio. Shell triangularly cordate, posteri<)rl\ 

 flexuously impressed and radiately grooved, ante, 

 riorly smooth ; dark oli\e. 

 Lea, Trans. Amer. Phil. Soc. ISiJi, Ohs. vol. i. p. ISO 



pi. 10. f. 2S. 

 Ilab. Tennessee, North America. 



Striately t;innved in a very <'liai'acteristic manner on tin 

 posterior side, wliieli is eoneavely llexnoiis. 



Species 59. (Mus. Cuming.) 

 10 pileus. Un. testa trir/oiw-cordatd, postice concavd. 



deinde jlexiioso-triincatd, Ittmgatd: lidescente-olivaced 

 viridi lineari-radiatd. 

 The cap Unio. Shell triangularly cordate, posteriorly 

 concave, tht>n llexnonsly truncated, smooth ; yellow- 



Lea, Train, .\iiur. I'liil. Soc. 1S30, Ohs. vol. i. p. U'.> 



Ilab. Ohio Kiver, Ninth Ameiiea. 



Reseniblin;;- U. S,iirrrbijaiiiis a good di-al in form. In 

 the posterior side does not present the eliaracteristic groo' 

 ing of that species. 



Species (!0. (.Mus. Cuming.) 



Unio SULCATUS. Un. testd oMongo-Donadfonui, uniice 

 brevissimd, postice coin/iressi: proditctd, Jlexnoso-im- 

 pressd, obsolete sutcatd ; lidescente-olivaced, fiisco-vi- 

 ridi lineari-radiatd. 



The gkoovei) Unio. Shell oblong-Donax-shaped, ante- 

 riorly very short, posteriorly compressly produced, 

 flexuously impressed, obsoletely grooved ; yellowish- 

 olive, linearly rayed with fuscous-greeu. 



Lea, Trans. Amer. Phd. Soc. 182!), Obs. vol. i. p. 4t. 

 pi. 8. f. 13. 



Hub. Ohio Kivcr, North America. 



Unusually short oi 

 eoinpressly produced 



iiiti rior side, the posterior 1 

 the manner of a Donax. 



September, 1864. 



