120 THE VOYAGE OF H.M.S. CHALLENGER. 



Venus ( Ventricola) casina, Liime. 



Venus casina, Forbes and Hanley, Brit. Moll., pi. xxiv. figs. 1, 5, G. 



Venus casina, Reeve, Conch. Icon., fig. 15. 



Veims casina, Sowevhy, Tlies. Conch., pi. clx. figs. 177-180. 



Hahitat. — Tencrife, Canary Islands, at a depth of 70 fathoms ; also Station 75, oft" 

 Fayal, in 450 fathoms. 



Only a single small valve was dredged at the latter localit}'. Mr. MacAndrew 

 obtained this species at Porto Santo, Madeira, and it is found in the Mediterranean and as 

 far north as Norway. 



Voms {Ventricola) effossa, Bivona. 



Vemis effossa (Bivona) Philippi, Moll. Sicil., vol. i. p. 43, jjI. iii. fig. 20, vol. ii. p. 34. 



Venus effossa, Deshayes, Cat. Conchif. Brit. ^lus., p. 100. 



Venus {Chione) (^Ventricola) effossa, Ittimcr, j\Ial. Blatt., 1867, vol. xiv. p. 124. 



Hahitat. — Teuerife, Canary Islands, in 70 fathoms ; also Station 75, oft' Fayal, Azores, 

 in 450 fathoms. 



Only a few odd valves of very young shells were obtained at the latter Station. In 

 this immature condition they do not exhibit the characteristic sunken lunula. 



Venus (Antigona) lyuerpcra, Linne, var. 



Venus puerpera, Linne, Mantissa, p. .545. 



Venus puerpera, Sowerby, Gen. Rec. and Foss. Shells, fig. 1. 



Venus pueipera, Sowerby, Tlies. Concli., p. 703, pi. clii. fig. 1. 



Venus j)ueipera, Eeeve, Conch. Icon., pi. iv. fig. 10. 



Venus 2Merpera, Pfeiffer, Conck -Cab. , ed. 2, p. 145, pi. 10, figs. 4, 5. 



Habitat. — Eeefs oif Tonga tabu, July 21, 1874. 



The shells from this locality differ only from the typical form of the species in having 

 no purple stain within the valves at the posterior end. In the British Museum a speci- 

 men from the Andaman Islands varies in the same manner, and others from the Fiji 

 Islands and Torres Strait are intermediate with respect to this coloration, having only 

 two small purple marks near the muscular scar. A character which appears to be pretty 

 constant both in the type and this variety is the V-shaped purple mark upon the ape.x of 

 the umbones. This feature I also find present in Venus resticulata, Sowerby, Venus cBgrota, 

 Eeeve, Venus lacerata, Hanley, Venus magnijica, Hanley, and would probably be met 

 with in young fresh specimens of Venus soioerhyi, Deshayes, and Venus clathrata, Deshayes. 

 In Venus crispata, Deshayes, and Venus listeri, Gray, it does not aj^pear to be present, 

 judging from the few .sj^ecimens examined. All the above-mentioned forms have the 



