THE SHELL- SLUG. 31 



soot-begrimed trees which in purer air and soil 

 would be the haunt of these and other woodland 

 species. 



Before leaving the garden, however, we may look 

 for the curious shell- slug, Testacella haliotidea (that 

 is, resembling a Haliotis or ear-shell), which is not 

 very rare in London gardens, although, from its 

 habit of burrowing, it is often overlooked. The 

 metropolitan form, however, is said to differ suffi- 

 ciently and permanently from haliotidea to warrant 

 its being regarded as a permanent variety, and it was 

 accordingly described by the late Mr. George Sowerby 

 as Testacella scutulum. To this variety probably 

 belongs the animal described by Mr. Tapping 

 (" Zoologist," 1856, p. 5105) as Testacella Medii 

 Templi, from its having been found under the 

 shelter of a south-west wall, in the Middle Temple 

 Gardens. Specimens have been procured from time 

 to time in the Botanic Gardens, Kegent's Park ; 

 in the Circus Road and Adelaide Road, St. John's 

 Wood ; at Hampstead, Hendon, Kensington, Ham- 

 mersmith, and Lambeth (PL II., fig. 6, 7). 



The animal partakes of the nature both of a slug 

 and a snail, having a long naked body, and a com- 



