PLATE XXIII. 



Fig. 

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2. 

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 6. 



9. 

 10. 

 11. 

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 14. 

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16. 

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18. 

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Page. 



SipJio Sabinii (Gray). Butley. (York Museum) . . .183 



Ditto. Pleistocene, Grettinge, Norway. (Christiania Museum) . 183 



Ditto. Little Oakley. (Harmer Collection) . . .183 



Sipho mmimus, sp. nov. Boyton. (Cambridge Museum) . . 189 



Si'pho Olavii, Morch. Little Oakley. (Harmer Collection) . . 193 



Ditto. Pliocene, Iceland. (Morch Collection) . . .193 



var. Morchii, nov. Little Oakley. (Harmer Collection) . 194 



ditto. Pliocene, Iceland. (Morcli Collection) . .194 



ditto. Little Oakley. (Harmer Collection) . . 194 



Slplt.o tortuosns (Reeve). Recent, Northern Seas. (Friele Collection) . 190 

 Ditto. Little Oakley. (Harmer Collection) . . .190 



Si2)ho tortuosus (juv.). Recent, Northern Seas. (Friele Collection) . 191 

 Ditto. Little Oakley. (Harmer Collection) . . .190 



Si2)hu Olavii, Morch, Yiir. eouulus, HOY. Waldringfield. (York Museum) 195 

 SipJto tortuosus (Reeve), var. turrita, M. Sars. Recent, Lofoten Islands. 



(Harmer Collection) ..... 191 

 ditto. Gedgrave. (Harmer Collection) . . . 191 



SipJio Menapias (A. Bell). Wexford gravels. (Jermyn Street Museum) 186 

 Ditto. Wexford gravels. (Jermyn Street Museum) . .186 



Ditto. Isle of Man. (Harrison Collection) . ■ .186 



NeptiLiiea ventricosa (Gray). Felixstovv. (Norwich Museum) . 171 



