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Study of Conchology on a firm Basis. Zool. Journ. 1824, 

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On the Anatomical Difference between Helix hortensis and 

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On the Natural Arrangement of the Puhnobranchous ]\Iol- 

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 into LimacidEe, Helicidse, Auriculadfe, Lymneadae, Onchi- 

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Some Observations on the Economy of Molluscous Animals, 

 and on the Structure of their Shells. In Phil. Transac- 

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A List and Description of some Species of Shells not taken 

 notice of by Lamarck. Annals of Philosophy, 1825. 



On some new Species of AmpuUariadae. Annals of Philo- 

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On the Structure of Pearls, and the Chinese mode of pro- 

 ducing them of a large size and regular form. Annals of 

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Remarks on the Difficulty of distinguishing certain Genera 

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On Clausium of Clausilia. Ann. and Mag. Nat. Hist. iii. 

 243. 



Genus Assiminia. Ann. and Mag. N. Hist. xvi. 183. 422., 

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On the Teeth of Perronia and Otina. Ann. and Mag. N. H. 

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On the Teeth of Testacella and Glandina. Ann. and Mag. N. 

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On Tongues of Mollusca. Ann. and Mag. N. H. x. 411. 



On Teeth of the Pneumobranchiate Mollusca. A'nn. and 

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On new Species of Spha3rium. A7in. and Mag. N. H. xvii. 

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On a second Species of Sphterium. Ann. and Mag. N. H, 

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Manual of British Land and Fresh-water Shells. 12mo. /^<^t) , 



