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distinguish it from other marine bodies, and send some of my speci- 

 mens to Ur. Carpenter, in the hope that it will enable him to add a 

 full account of its formation and structure to his paper on the Fora- 

 miniferous Shells which he is preparing for the Transactions of the 

 Royal Society, assisted by the funds of that Institution. 



1. Carpenteria. 



Shell conical, attached by the broad base, formed of a series of 

 elongated cells, each ending in a contracted mouth, piled one against 

 another in a spiral manner, and with the aperture of the last cell 

 at the apex in the centre of the acute cone. The substance of the 

 cellj is formed of a network of calcareous anastomosing ribs ; the 

 interspaces between the ribs are thin, calcareous, prominent exter- 

 nally, and pierced with numerous perforations. The cavity of the 

 cells is filled with a fleshy sponge-like body, strengthened by nume- 

 rous minute, simple, pin-shaped and fusiform smooth spicula placed 

 in bundles. 



C. BALANIFORMIS. 



Hab. Philippine Islands, on Porites, Cardita, Pec ten and other 

 shells. 



The conical shell is furnished with a single contracted aperture 

 at the apex of the cone ; as each cell is formed it closes the aperture 

 of the preceding cell, so that only one is seen at the top of the cone. 

 Some specimens show two or rarely three apertures at the tip of the 

 cone ; but this arises from the tip having been broken ; these aper- 

 tures are of a larger size and irregular form, very unlike the con- 

 tracted uniform-shaped aperture of the last cell. 



When the shell is worn, or partly destroyed by acid, the thin part 

 between the network is destroyed, leaving only the calcareous ribs, 

 which fill the greater part of the cavity, leaving a cavernous calca- 

 reous body somewhat like a sponge turned into stone. 



A section of the parietes of the cells appeared to be formed of 

 polyhedral plates separated from one another by a rather opake line, 

 as if formed by the union of the edges of the plates ; and each plate 

 is pierced with a number of uniform-sized, regularly disposed cir- 

 cular perforations, leaving a nearly uniform imperforated belt round 

 the margin of each plate. 



The specimens on the shells of Cardita variegata from the shores 

 of the Mediterranean are so different in substance and structure 

 from those found (on the same species of shell among others) on 

 the shores of the Philippines, that I propose to form for them a 

 second genus, named in honour of M. Felix Dujardin, the Professor 

 of Biology and Dean of the Faculty of Sciences at Rennes, who first 

 described the animal of the many-chambered microscopic shells, 

 which had before been generally considered as the residence of 

 Cephalopoda] the most complicated organised mollnsca, instead of 

 the most simply organized animal. 



