211 



IrivoJuU, and was ohtjiiru'd Worn liiiko Huron I)y Mr. Racket, 

 whose name liad \)w\\ previou.sly iippluid in lliis ^unurt Ity Hriird. 

 in the Ann. du MuHouni, vol. II. 



Tt IH reniarkablo Unit. Sowciilty 1ms ropnistintcMl (his mxicicK 

 under tlu; name of /nairiiifi/ns, a|i])ar(!iilly willioiii, Ixiin/:; iiwan; 

 that I hud previouHly dcscribod il, under tlici winjo nanii!. I'l. .M, 

 fig. 8. 



Ltmnkiis Ki\lAl{(llNA'l'lis, >S'. Jimrii. AruuL Nal. Sci. vol. 1, 



p.no. 



Ohs. In }^(^n(M-al olxrsity i(. has a, res(!nil)laji(!() to L. iu/ldlUK, 

 JJrong. It was lirMtwjnt to nu; l»y IVlr. Aaron Stone I'roni the; liik(!S 

 of Mairu!. Dr. IJig.shy prcHcnted nie. witli a M|)(H!inien vvhieli he 

 obtained in njjper (lanada,, and F hav(! ree(!ntly n^eeivcid neveral 

 from Mr. Titian l'(;a,l(!, alwo found in Maine, one of whieh i^ 

 doubl(! the size of the figure represented in our IMato 55, fig. I. 



JiljMNKIIH (!ATAHf1()l'IIIM, S. Atticr. I'J<L of NirliokoiiH ['liirifcl. 

 A rtidc (!()ii<:lud()<ji/. 



Obn. Its European analogue is the /y. jMrcfj/rtmi, \j., from 

 whieh it may be distinguished by a d(!(!p<!r fold of the coluirKjIlu, 

 and a more aeute eurvatiir(! of the inlerior portion of the ayier- 

 ture. I'l. 55, fig. 2. 



LiMNKDH Di'.ci DIOHIJH, /S'. Journ. Aai'l. Ndl. Set. vol,. 2, p. I (lt». 



OLh. My ))n»ther, J{. Say, snbH(!(jiienlly asefirfained it to be an 

 iidial)itant of Pennsylvania; found also lusar New Harmony by 

 LesiKMir. 1*1. 55, fig. '{. 



I'kctkn. — Shell fre(!, bivalve, in(;(juivalve, thin, aurieulated, 

 equilateral ; hinge margin transverse, reetilinear, eonnect(!d 

 throughout by a ligament, the cartilage b'iing inferior, fixed in a 

 triangular fosset of eaeh valve, under the apex ; apices c(jntiguouH, 

 not elevated ; muscular impression largo, subeentral ; palleal im- 

 pression without sinus : animal subor})i(;ular ; foot very small, some- 

 tim(!s with a byssus ; mantle fringed with tenta-eular papilhe, of 

 whieh the scries is iriterrupted somewhat regularly by shorter 

 cylindrical proc«!Hses ttirminating in oeuliform disks; mouth large, 

 transverse, surrounded with fringed lobes, and with a thin lam(d- 

 lated palp on each side ; anus free ; branchiiw largr;. 



Ohn. The numerous species of shells which form this very 

 beautiful and natural genu,s, inhabit alirio.st universally the mar- 

 gins of the marine portion of the gIob<;, from the torrid zone to 



