285 



THE LAND AND FRESHWATER SHELLS OF THE 

 CHANNEL ISLANDS. 



Ey J. R. BROCKTON TOMLIN, M.A. and E. D. MARQUAND, A.L.S. 



(Read Ijefore the Society, November 12, 1902). 



The following list embodies the result of our researches during manj^ 

 years past, chiefly in Guernsey and Alderney. It will perhaps serve 

 as a convenient foundation-list to which additions can be made from 

 time to time. The slugs of the smaller islands have hardly been 

 touched, and it is more than probable that this branch of the subject 

 would repay investigation. The Jersey records are mostly taken from 

 two papers by Mr. E. Duprey.^ 



The Channel Islands differ considerably in size. Jersey is nearly 

 twice as large as all the others put together, having an area of sixty- 

 two square miles. Guernsey has an area of twenty-four square miles, 

 Alderney about four square miles, Sark a little less, Herm and Jethou 

 still smaller. The rocks are chiefly igneous, but some ancient sedi- 

 mentary strata occur in Jersey and Alderney. Guernsey consists of 

 gneiss and quartz diorite, with a little granite. Sark is composed of 

 gneiss and hornblende schist. No limestone occurs in any of the 

 islands, but veins of calcite are found. The climate is exceptionally 

 mild and equable, and the rainfall less than that of Devonshire and 

 Cornwall. 



The number of land and freshwater shells recorded for the Channel 

 Islands in the present paper amounts to seventy-three species. 



Testacella maugei F^r. — St. Saviour's Road, Jersey, of not 

 infrequent occurrence (Duprey). 



T. SCUtulum Sow. — Not uncommon in gardens in the vicinity of 

 St. Peter-Port, Guernsey. Common in the Seigneurie grounds, Sark 

 (Cooke & Gwatkin, as T. haliotidea). In Guernsey the late Dr. Lukis 

 was acquainted with Testacella as early as 1801, as .it inhabited his 

 garden at the time, and was afterwards discovered at the end of the 

 valley in which his garden was situated {/. Conch. ^ vol. 5, p. 346). 



Vitrina pellucida Miill. — Common, especially in Guernsey and 

 Alderney. Oar observations tend to show that these shells all belong 

 to a form which is flatter and proportionately more elongate tlian the 

 type — generally considered on the continent a distinct species, and 

 figured by Clessin as the var. eUiptica Brown.- A fine Guernsey speci- 

 men measures 6 mm. by 2-5 mm , and an Alderney one 6 '5 mm. 



Limax maximus L. — Jersey (Duprey). Guernsey, not infre- 



1 Ann. and Mag. Nat. Hist. (4) vol. 18, p. 338-345, 1876, .ind (5) vol. 11, p. 1S5-190, 1883. 



2 "Deutsche Excursions Molkisken Fauna," ed. 2, p. 70, 1884-5. 



