Sept. 1, 1SG6.] 



HABDWICKE'S SCIENCE-GOSSIP. 



195 



SNAILS AND THEIR HOUSES. 



A S there is no creature more common on our 

 -*-*- chalk and limestone, as well as on our silieious 

 or sandy soils, than the genus Helix, so there is none 

 which authors have taken greater pains to classify 

 elaborately. These "common things " belong to the 

 Malacozoa or Mollusca. Blainville gave them the 

 one name (from iiialakos, soft, and zobn, animal), 

 and Cuvier gave them the other and more convenient 

 term— "soft things." He also pronounced them 

 gasteropods, or belly-footed, because they possess a 

 muscular disk or foot for creeping, attached to the 

 body underneath. Slugs, however, as well as snails, 

 and even marine whelks and buccines, — indeed, all 

 ordinary mollusks, are familiarly known also to 

 possess this fleshy appendage. But then Helix is 

 the Latin for snail, as Dr. Johnson declares face to 

 be that for a candle, and it stands to reason that 

 Helix should be distinguished as the snail par 

 excellence ; aud it is so regarded both by Linnseus 

 and Lamarck. 



The three most familiar to us from their shells 

 are : — 



Fig. 174. Spotted Snail (H. aspersa). 



H. aspersa, or Spotted Snail (figs. 174, 175], the 

 most common of all, whose four brown bands are 

 interrupted by yellow curved spots. 



Fig. 175. Spotted Snail (H. aspersa). 



H. nemoralis or arbastorum, the Wood or Orchard 

 Snail (figs. 176, 177), brown, and marbled with 

 yellow, with one long dark brown band continued 

 from the spne to the base of its volutes. 



H.hpriensis 3 the Garden Snail (fig. ISO), avery pretty 

 yellow shell, with five longitudinal brown bands* 



* Some authors regard Helix nemoralis and H. arbustorum 

 as distinct species, with H. hybrida and H. hortensis as va- 

 rieties of R. nemoralis. 



Of these the first is the larger and more destruc- 

 tive : ask the gardener. Fortunately, however, it 

 is so sensitive to cold, that, whilst carrying large 

 and commodious premises upon its back, it takes 



Fig. 176. Wood Snail [H. nemoralis). 



care to shut itself up in them (closiug over ^the 

 aperture with a film, as also does the wood snail) at 

 the least sensation of frost or discomfort. Thus 



Fig. 177. Orchard Snail (H. arbustorum). 



children, who are sometimes wonderfully observant 

 naturalists, taunt it with the rhyme, — 



" Snail, oh snail, shoot out your horn, 

 And show 'twill be a good day the morn." 



Unquestionably the snail will not exhibit a single 

 tentacle, of which it has four, unless to confirm a 

 favourable prognostication of the weather. 



A 







Figs. 175, 179- Apple Snail {H. pomatia). 



When we speak of size, the most respectable 

 British suail is the Apple Snail, H. pomatia (figs. 178, 



K 2 



