84 



Journal of the Kentucky Academy of Science 66(2) 



Figure 2. Typical five-striped wood snail morph. There 

 is such great variation in shell striping for this species that 

 a coding system has been developed to catalogue it (Howe 

 1898; Jones et al. 1977). Stripes are numbered from top 

 to bottom. This shell would be coded 12345. A shell with 

 only the third stripe present (Figure 3) would be 00300. 

 When partial or total fusion of bands is taken into account, 

 there are hundreds of possible variants. 



which are common in their habitats, and avoid 

 species with high concentrations of secondary 

 compounds or physical defenses against her- 

 bivory such as hairs (Grime et al. 1968; 

 Thompson 1996). Oddly enough, they are said 

 to particularly favor the leaves of stinging net- 

 tles (Step 1901). They are adaptable in the lab 

 or under cultivation and happily eat lettuce, 

 carrots, fruit, pure cellulose filter paper, and 

 even (occasionally) mutton (Grime 1968; Judd 

 1953; Murray 1964; Sowerby 1825; Thompson 

 1996). 



Though these snails lack operculums which 

 would allow them to close their shells, they 

 have a relatively high drought tolerance due 

 to their ability to aestivate. After feeding, they 

 generally crawl up onto the plant or a nearby 

 shrub or stone wall, stick themselves dovm 

 with a dab of slime, and remain inactive until 

 the next moist evening. During dry spells, 

 these organisms can remain dormant for long 

 periods of time until conditions improve. (Aes- 

 tivation in many species of snails can last for 

 months, and even for years in some [Abbott 

 1989].) For the winter months, the snails bury 

 into the soil and remain dormant until spring 

 (Lovell 1884). 



In Great Britain, song thrushes can be a 

 major predator of adult wood snails, crushing 



their shells on stones to get at the soft snail 

 within. Other birds, including chickens, will 

 sometimes eat wood snails (Howe 1898). Sev- 

 eral snail predators are invertebrate organ- 

 isms, including certain beetles, glowworm lar- 

 vae (related to fireflies), and even predatory 

 snafls (Jones et al. 1977; Woodward 1913). 

 Small mammals such as shrews, moles, and 

 hedgehogs also enjoy these slow-moving mor- 

 sels (Dees 1970; Reed 1964; Woodward 1913). 



SPREAD IN THE U.S. 



Since the arrival of Europeans, many spe- 

 cies of molluscs have been both purposely and 

 accidentally introduced into the U.S. In recent 

 years, the number one pathway for the intro- 

 duction of new land snail species seems to be 

 via infested horticultural materials (Cowie and 

 Robinson 2001). Eggs and small individuals 

 such as juveniles can be difficult to see when 

 intermixed with soil, mulch, or other plant ma- 

 terial (Cowie and Robinson 2001). Many snail 

 species can also self-fertihze or store sperm 

 for up to a year after mating, so one over- 

 looked adult may be all it takes to pioneer an 

 invasion (Gowie and Robinson 2001; Thomp- 

 son 1996). Wood snafls specifically have also 

 been found by the US DA stuck to vehicles 

 and military cargo (Dundee 1974). 



The helicid snails, which include C. nemor- 

 alis, have a somewhat more colorful history of 

 introduction, as many of these were purposely 

 established in new habitats (Dees 1970; Mead 

 1971). Helicids, such as Helix pomatia, the 

 French escargot, are often prized as choice co- 

 mestibles. Many helicid introductions can be 

 traced back to the kitchen gardens of Euro- 

 pean immigrants desiring a renewable source 

 of snails (Mead 1971). 



As a small and unusually colorful species, C. 

 nemoralis has the distinction of being more 

 often introduced for ornament than for food. 

 The earliest U.S. introduction of this species 

 was made by malacologist William Binney in 

 1857 (Pilsbry 1939). Binney collected snails in 

 Sheffield, England, returned to the U.S. and 

 then released them in his Burlington, NJ, gar- 

 den, where they proceeded to flourish (Binney 

 and Bland 1869). 



The U.S. populations of C. nemoralis orig- 

 inate from multiple sources, however. A Lex- 

 ington, VA, population was attributed either to 

 an introduction of Italian snails in packing ma- 



