644 



sulcata, albida, fasciis stramineis et punctis rubris, vel grisea, ma- 

 culis rubescentibus seriatim dispositis biradiata, vel aurantiaca, 

 fulvo radiata ; intiis purpureo et aurantio varie picta ; latere an- 

 tico brevi, declivi, lunula subdistincta ; latere postico oblongo, 

 quadrato, margine dorsali paululum declivi, ad ligamentum vix 

 recedente. 



Shell oblong-oval, rather squared posteriorly, with fine, blunt, 

 not quite continuous sulci, various in colouring, generally speckled 

 and radiated, and painted within with orange and purple ; anterior 

 side very short and sloping, with the lunule not very distinct ; 

 posterior dorsal margin full up to the hgament. 



Eed Sea. Varieties, fig. 165, Mr. Cuming's collection, fig. 166 

 and 168, Mr. Gubba's. 



109. Cyther^a lentiginosa (pi. cxxxv. f. 160, 161, 162), 

 Chemnitz, Conch, f. 1963, 1964. C. Pfeifferi, Fhillppi, Abbild. 

 t.9. f. 1. 



Cyth. testa ovali, subventricosa, obtusissime concentrice sul- 

 cata, sulcis subundulatis, fusca, vel pallide fulva, grisescente, ma- 

 culis et lineis nigrescentibus praecipue ad margines picta, ad um- 

 bones purpurascente, intiis griseo nebulata ; umbonibus obtusis ; 

 lunula subcomplanata ; area dorsali excavata. 



The grooves are more obtuse and less numerous than in C. Ara- 

 bica ; the shell is more oval, the umbones not quite so prominent, 

 and the dorsal area is hollow. The colour is brown or yellowish, 

 tinted with purpHsh-grey, particularly inside and at the umbones ; 

 at the edges all round there are diverging lines composed of 

 blackish spots. 



Red Sea. 



110. Cyther^a abbreviata (pi. cxxxv . f . 1 7 0, 1 71), Lamarck, 

 Anim. s. vert. C?/t/i. no. 62 ; Delessert, Recueil Choisi, t. 9. f. 1. 



Cyth. testa C. Arahica. simili, sed breviore, antice quadrata; 

 sulcis acutiusculis, magis distantibus, integris, contiuuis. 



In the two rather difi'erent-looking shells which we figure under 

 this name, the back part is much shorter and more squai'e than in 

 C. Arahica : this might be accidental, but the grooves are also 

 more distant and sharp, and all continuous. 



Indian Ocean, Lamarck. Var. fig. 170, Mr. Sowerby's speci- 

 men ; fig. 171, Mr. Gubba's. 



111. Cyther/ea subelliptica (pi. cxxxv. f. 169), Sowerhy, 

 juu. 



Cyth. testa ovali-rotundata, ventricosa, distanter concentrice sul- 



