CYAMIUM. 263 



old, and continued in a torpid or quiescent state even 

 after they had been provided with a fresh supply of 

 water. In this state, however, the shells were partly 

 open, and the Cyamia were still feeding. The fry are 

 enveloped in irregularly oval gelatinous masses, each 

 containing from 12 to 20 individuals. These spawn- 

 masses are deposited on extraneous substances; so 

 that the animal is not viviparous. The fry are found 

 in various stages of development ; but in every state the 

 shells are perfectly formed and can be seen through the 

 transparent envelope. 



Fleming, in his ' British Animals/ seems to have mis- 

 taken this species for Lascea rubra. It is the My a pur- 

 purea of Montagu. Brown placed it in the genus Saxi- 

 cava, Deshayes in Chione, and Moller in Lescea. 



In some shell-sand dredged for Dr. Lukis at about 

 20 fathoms, on the east coast of Guernsey, and within 

 two miles of the land, I found not only a living CVzr- 

 dium papillosum and other rarities, but also a young and 

 perfect specimen of Cardita lithophagella of Lamarck. 

 It is the Byssomya Guerinii of Payraudeau, and is not 

 very uncommon in the Mediterranean. In all probabi- 

 lity it belongs to the genus Cypricardia. Lamarck, in 

 describing this genus, says that it has three cardinal 

 teeth and one lateral, and that Cardita has only one 

 cardinal and one lateral tooth. But the present species 

 has two cardinal teeth, and one posterior lateral tooth, 

 in each valve, besides an anterior lateral in the left 

 valve. The pallial scar is deeply sinuous or indented at 

 the posterior side, and the muscular scars are of enor- 

 mous size. In these respects it would come nearer to 

 Venerirupis. The ' Journal de Conchyliologie ' for 1850 

 has an able article by M. Mittre on this species, in which, 

 however, he erroneously considered it to be the Cypri- 



