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or tail of the soft parts. Only two species are known, one inhabiting 

 Britain and the Channel Islands,* and the other the Canary Islands. 



Species. 

 1. haliotoidea, Draparnaud. 2. Maugei, Be Ferussac. 



Genus 2. LIMAX. 



Animal ; elongated or oblong, semicylindrical, rounded or cari- 

 nated posteriorly, anteriorly furnished with an oblong disc, in 

 which is imbedded an ungmforni shell ; head with four tentacles, 

 the two upper ones furnished with eyes. (Forbes.) 



Shell ; subquadrate, irregidar, subcrystalline, with an umbonal 

 nucleus, covered with an epidermis more or less reflected over 

 the sides. 



Most of the known species of slugs are of this genus. The small, vo- 

 racious Limax agrestis, the pest of our gardens, or the larger L. cinereus, 

 taken as types, may be observed to have a kind of fleshy shield over the 

 back of the neck, and in this is concealed a small crystalline shell of 

 oblong-square form, not convoluted, but secreted in concentric layers from 

 a kind of umbonal nucleus. So little attention has been paid to these al- 

 most shell-less mollusks, that few observations have been made of their ex- 

 istence in foreign lands. Lamarck only described four species of his own 

 country. M. Deshayes, in his edition of Lamarck's work, increased the 

 number to nineteen, including four from New Zealand, Ascension Island, 

 and Mauritius, observed by MM. Quoy and Gaimard, and one or two from 

 Carolina, Madeira, and Teneriffe. We have in Britain eight species, two 

 of which are found in the Eastern United States, near the sea, probably 

 transported thither. Two aboriginal species, distinct from the British, 

 have been described from the Western States. 



Species. 



1. agrestis, Linn. 3. Alpinus, Lam. 5. Ascensionis, Quoy. 



2. albus, id. 4. arborum. Bonch. 6. bitentaculatus, id. 



* Testacella haliotoidea has been collected in the neighbourhood west of London ; Mr. 

 Sowerby found it in a garden at Lambeth, and I once captured a specimen crawling into a con- 

 servatory at Waudsworth. 



