aiazatlax bivalves 81 



Family ASTAETID^, 



C3i)rinid£e, Forhes, Woodtv. This name lias been previously 

 appropriated for a family of Fislies. Gray divides it into 

 four families, Carditida?, Astartid^, Crassatellidee, and Glos- 

 sidje (Isocardia, Lam.) 



Genus CIECE, Schum. 



Cytherea (pars) Lam. — This genus is ranked witli the Veueridse 

 by Gmi/ Sf Desk., with Astarte and Cjiprina by Forhes and 

 Woodto. 



114. ClECE MAEGAEITA, n. S. 



C. t. minima, suhovali, in<squilaterali, umhonihus appressis, 

 suhruyosis, concentrice lirata, liris acutis, area lumtldque 

 indistinctis, ligamento celato : parte anteriori dilatd, 

 posteriori parvd ; dente laterali antic o maximo, altera in 

 valvd in cardinalem confluente ; postico lorujo, exili : cardinali- 

 bus 2-3 ; impressionihus miiscularihus, sulaqualihus, lined palUi 

 a margine remotd ; alhd Jlavescente, dentihus puipureis ; epi- 

 dermide tenui. 



This genus abounds in the Eed Sea, Australia and the East 

 Indies generally. It has not been described from the American 

 coast, i have several species in a collection sent from the U. S. 

 as from S. America ; but as nearly all are identical with Aus- 

 traban species, the locabty is probably erroneous. The charm- 

 ing Uttle C. margarita however establishes its claim to a place 

 in the genus, by its appressed, somewhat rugose umbos, semi- 

 internal ligament, large anterior tooth, and the pallial line 

 which, though generally indistinct, is certainly not sinuated. 

 It is oval, with very delicate, rather sharp concentric lines, 

 covered witb a thin epidermis ; sometimes subdiaphanous, 

 sometimes opaque and yellowisli inside, with a purple tinge 

 on tbe teeth. It may be the young of a larger species not yet 

 discovered, but as about a score of specimens were foimd fresh, 

 nearly of the same size, and with the rugose portion of the 

 umbos clearly distinguished, it may not improbably be adult. 

 Long. "Oo, lat. '07, alt. '03. 



^«i.— Mazatlan ; on Spondylus Lamarekii, very rare ; L'pool 

 Col. 



Tablet 412 contains 1 pair closed ; 2 do. open, (the largest 

 and smallest,) and 1 yeUowish valve. 



