CYRENA. BATISSA. 207 



conical and the posterior are somewhat elongated and flattened. 

 The striae are more or less obsolete. The epidermis is light green 

 and polished. The ligament is narrow, elongated, and not 

 prominent." 



The only specimens of this species which the author has been 

 able to see are those in the British Museum, two in number, 

 which, though they agree well with Prime's description and figure, 

 are much smaller, having soinewhat the appearance of young 

 specimens ; their measurements being as below : 



1. 2. 



Long 43 46 mm. 



Lat 47-5 49 mm. 



Diam 24 24-5 mm. 



331. Cyrena galathese (Morch). 



Cyrena (Corneocyclas) (jahithea (Reinhardt MS,), Morch, Cat. 



Conch. Kierulf, 1850, p. 32, pi. 2. 

 Cyrena yalathea, Prime, Cat. Corb., 1863, p. 6 ; 1869-70, p. 144, 



no. 33. 



Original description : Testa cordato-trigona, insequilatera, 

 turgida, concentrice striata, postice longiore, truncata, antice et 

 inferne angulata, umbonibus distantibus, prominentibus ad 5 

 anter. sitis ; lunula rhomboidali, medio carinata ; area lanceolata, 

 convexa, ligamento tumido duplo longiore. Dentibus lateralibus 

 interne fovea impressa ; d. 1. posteriore v. sin. triangulari 

 compresso ; pone ligarnenturn sito ; d. lunulari v. s. conico, 

 dentibus cardinalibus aproximato. Dentium cardinalium 2 

 anterioribus v. s. et 2 posterioribus v. d. bifidis, dente card, 

 posteriore v. s. lineari, v. d. obsolete. Limbo augusto, nitido. 

 Impressione musculari semilunari, posteriore rhomboidali, duplo 

 majore. Colore albo, dentibus cardinalibus et fundo cavitatis 

 flavescentibus. Epidermide nigrescente, antice radiis obsoletis. 



Long. 100, lat. 120, diam. 74 mm. 



Hab. Galatea River, ]S"icobar Islands. 



Genus BATISSA. 



tiatissa, Gray, A. M.N. H. ser. 2, xi, 1853, p. 38. 



Cyprina, Cyclas, Bruguiere, Encycl. M3th. 1792. 



Cyrena, Lamarck, Anim. s. Vert, v, 1818, p. 553. 



Venus, Gray, in Wood, Index Test., Suppl. 1828, pi. 2, fig. 13 : 

 Deshayes, Cat. Brit. Mus. 1854, p. 219 ; Prime, Cat. Corbiculida^ 

 1869-70, p. 138 ; Clessin, in Martini & Chemnitz, Conch. Cab. 

 1879, p. 206. 



TYPE, Batissa tenebrosa, Hinds, from the Fiji Islands. 

 Range. Nicobar Islands ; Malay Archipelago ; N. Australia and 

 Tropical Islands of the Pacific. 



