31 



Figure. 



AcMyEA gigantea. PL 24. Fig. 142. Shell, showing the interior of an 

 unusually large species. 



Genus 6. GADINIA, Gray. 



Animal ; head distinct, flattened ; tentacles expanded, funnel- 

 shaped ; eyes sessile ; foot flat, thin, simple, f Adams J 



Shell ; rotundately conical, smooth or rayed, sometimes rather 

 solid, whitish. 



This genus, more generally known to collectors by Mr. Sowerby's name 

 Mouretia, has a peculiar whitish roundly conical shell, while the animal 

 differs from that of Acmcea in having the tentacles expanded and funnel- 

 shaped. The species are as yet but imperfectly known, and only the fol- 

 lowing have been described. 



Species. 



1. Afra, Gray. 3. Garnotii, Payr. 5. reticulata, Sow. 



2. costata, Krauss. 4. Peruviana, Sow. 6. stellata, id. 



Figure. 



Gadinia Peruviana. PI. 24. Fig. 143. Shell of a solid, broadly conical 

 form, showing the interior, with its horse-shoe muscular impression. 



Order 5. CYCLOBRANCHIATA. 



Branchiae ; placed round the body in a circle, between the mantle 

 and the fool or disc. 



In this Order are brought together, after the method of Cuvier, two 

 families possessing very differing kinds of shell, but in the animal of each 

 there is a similarity in the arrangement of the branchiae. The branchial 

 plume, which in the preceding family is lodged within a cavity of the 

 neck, is in the Patellacea modified into an elongated cord of plates ex- 

 tending round the body between the mantle and the foot ; and the same 

 arrangement obtains in the Chitonacea. There is, however, something 



