UNIO.— Plate XLU. 



The Camelopahd Unio. !?hell oblong, wide, com- 

 pressed, ratlier angular at the back, obliquely trun- 

 cated, white, thick within, yellowish -olive without, 

 ornamented with green squarish spots disposed in 

 rays, anterior side short, rather narrow, ventral mar- 

 gin rather straight, inflated a little posteriorly, pos- 

 terior side wide, oblong, dorsal margin elevated, 

 slightly arched, with a posterior angle, umboes small, 

 compressed. 

 Lea, TJnio, vol. viii. p. 37. pi. lix. f. 180. 

 Hah. North Alabama ; Prof. Tuomey. 



Although this species is painted something in the manner 

 of U. pictim, it is a very different shell, being more com- 

 pressed, solid, and quadrate. 



Species 233. (Fig. b.) 



Umo Lindsleyi. Vu. testa lievi, compresm, solkld, el- 

 liptlcd, lata, postice biamjulatd, in/us alba, extus 

 nlivacco-lntescente, niacuUs viiirlibm subqtiadratis ra- 

 iVmthii dhpiisilit nriKild. hilcri' aiitico brevissimo, sub- 

 iDKiiisliihi, Uiti'i-f /."s/irij iililtiiiijo. lata, prupe angidum 

 Miiiiir i,irr<is.siitn, „i n-ijiii,' rf-iitniti injiato. 



Lindsley's Unio. Shell smooth, compressed, solid, ellip- 

 tical, wide, posteriorly biangulated, white within, 

 yellowish - olive without, ornamented with green 

 sciuarish spots disposed in rays, anterior side very 

 short, rather narrow, posterior side oblong, wide, 



obliciuely thickened near the angle, ventral margin 



inflated. 

 Lea, Unio, vol. viii. p. 33. pi. Iviii. f. 17(i. 

 Hub. Tennessee ; President Lindsley. 



The difference in outline between this and the preced- 

 ing species is easily observable, and there is a peculiar 

 thickness near the posterior slope. 



Species 234. 



I'mo Batavus. Un. tfMd temti, influtd, valdc iiueqiii- 

 laterali siibjlexuosd, postice obscure bianyiiluld, inhix 

 iilbo-caridescente, extus sordidi olivaced, tiil unibuiwa 

 plicis subatigulatis elecatis riKjatd, latere autico brevi, 

 angusto, luargine ventrali autice siibcontracto, postice 

 inflato, latere postico lato, margine dorsnli ehvnto, 

 rerdusciilo. 



The Batavus Unio. Shell thin, inflated, very inequi- 

 lateral, rather flexuons, posteriorly biangulated, bluish- 

 white within, dnll-olive without, wrinkled at the um- 

 boes with subangular, elevated plaits, anterior side 

 short, narrow, ventral margin rather contracted in 

 front, inflateil posteriorly, posterior side wide, dorsal 

 margin elevated, rather straight. 



Lamarck, Anim. sans vert. Unio xxxiii. 



Ilab. River Seine. 



More inflated, wider, and more obtuse at the exlreniilie.s 

 than U. uidunim. 



