INTRODUCTION. 51 



1. Assiminia Grayana. 



2. Bithinia ventricosa. 



3. Arion hortensis. 



4. Zonites crystallinus. 



5. nitidulus. 



6. radiatulus. 



7. . lucidus. 



8. pygmaeus. 



13. In 1822, Dr. Turton, in his work on bivalves 

 added 



1. Pisidium pusillum. 



14. In the same year, Mr. Miller, in his List of Shells 

 about Bristol, with three noticed in the former list, 

 added 



1. Zonites alliarius. 



15. In the same year, M. Ferussac, in his Prodro- 

 mus, added, 



1. Pupa anglica, sent him by Mr. Bean. 



16. In 1825, the Rev. Mr. Sheppard, in his List of 

 Suffolk Shells, added 



1. Vertigo edentula. 



2. Planorbis carinatus, var. deformis. 



3. Pisidium Henslowianum. 



17. In 1826, Dr. Turton, in his Conchological No- 

 tices, in the Zoological Journal, added 



1. Cyclostoma simile Drap., if not Bithinia ventri- 



cosa. 



2. Cyclostoma acutum Drap. 



3. Limnaeus scaturiginumrzLim. stagnalis Junior. 

 All shells which it is impossible to determine; and 



D 2 



