ZOOLOGY. 239 



The pier rock of Bona Vista was characterized by Vermes, and the 

 Spondylus gsederopus : in the grit rock we found the Cassis testiculus, 

 the same Spondylus as in the pier rock, several species of Fissurella and 

 Patella, and immense quantities of the bones of Asteriae. Imbedded in 

 the sand, were the Cassis testiculus, the Area senilis, the Cerithium 

 obelisticus, the Bulla striata, a Conus, a Buccinum, a Chama, and a 

 Purpura. In the tufa, we met with the Area senilis, the Mactra alba, a 

 Cerithium, a Modiola, and Vermes, all thinly scattered ; but there was a 

 very rich deposit in a conglomerate of sand and lime, which abounded at 

 a little distance from the shore. It contained the Cerithium obelisticus, 

 the Cassis testiculus, the Bulla striata, a Natica, a Buccinum, a Conus, the 

 Area senilis, the Lucina Pennsylvanica, the Tellina lacunosa, a Cardium, 

 probably the isocardia, a Mactra, an alba? a Cypricardia? a Venus, 

 a Solen, and an Ostrea. 



The shells which we found at St. Jago and the Gambia, were all in a 

 decidedly recent state, and are contained in the following list, and chiefly 

 named after Lamarck. 



Sepia officinalis, Bona Vista. 

 Balanus tintinnabulum, Gambia. 



,, porcatus? attached to the Scutella digitata. Gam. 

 Anatifera striata : Anatifa, Lamarck, Atlantic. 

 Pholas clausa, Grat/, Gam. 

 Solen truncatus. Wood, Gam. 



,, strigilatus, varietas, Gam. et B. V. 

 Mactra polita, Chemnitz, Gam. 

 Petricola guinaica, Gray, B. V. 

 Tellina lacunosa, B. V. and St. Jago. 



,, nivea, Chemn., Gam. 

 Lucina squamosa, B. V. 



,, Pennsylvanica, B. V. 

 Donax rugosa-, B. V. and Gam. 



„ truncata, Gam. 



