PLATE XVII 



1. Scalaria. 



2. The female Fivipara taken out of its shell, and the branchial cavity 

 h. The orifice of the womb. 



i 



r 



part situated under the spire 

 anus. 



canal of viscous matter, 

 projecting line, forming a se- ( 

 mi-canal, which terminates 

 at the siphon d. 

 heart and its auricle, 

 parts of the liver and intestine 



opened. 



a. The foot folded in two. 



b. .. operculum attached to its ^ 



posterior part. 



c. .. head, with the tentaculi 



and trunk. I, 



d. little siphon prolonged 



under the right tenta- 

 culum. 



e. .. lateral membrane of the 



left side. 



f. . . edge of the mantle. 



g. .. branchiae. 



h. .. womb swelled by the foe- 



tus within. 



3. Trochus. (Cochlea sublivida, Lis.) 



h. The head. I p. The languette. 



tt. .. tentacula. I P. foot. 



ee. .. eyes. \ o. . . operculum. 



4. Do. seen underneath, 



/. The foot. | m. The mouth. 



5. Animal of the Tmchus pharonius, taken out of its shell, with its oper- 



culum. 



6. 7 Turbo littoreus. 



S. 9. 10 Turbo chrysostomus. 



H Nerita canrena, taken out of its shell. 



■ . . - Nerita exuvia, with its operculu 



13 Tmchus, Gualt. 



13. Tivchus Levis, list 

 h. The head. 



ee. .. eyes. 



U. .. tentacula. 



p. .. male organ. 



14. Purpura- 

 h. The head. 



foot. 



filaments. 

 . operculum 



| T. The trunk. 

 I/?. foot. 

 tt. .. tentacula. | o. .. operculum. 



15. Buccinum undatum, half the natural size, seen on the left side ; the 



trunk drawn in, and the male organ turned back, and hidden in the 

 branchial cavity. 



a. The male organ. | e. The position of the heart, 



c. .. siphon. I J". mucous plates placed to the 



dd, ■■ position of the branchia?. | right of the branchiae. 



16. Buccinum undatum, with the trunk and male organ extended, 



a. The male organ. 



b. .. trunk. 



c. .. siphon. 



17. Natica . . Fossar, 

 h. The head. 



eyes. 



fleshy appendages at the 

 base of each tcntaeu- 

 htm. 



magnified. 

 tt. The tentacula. 

 o< . . open 



culum. 



nr. The mouth . 



$j' .. foot. 



