176 HELICIDJi:. 



2. H. aculea'ta"^, Miiller. 



H. aculeata, Miill. Verm. Hist. pt. ii. p. 81 ; F. & H. iv. p. 74, pi. cxvii. 

 f. 5, 6. 



Body rounded in front and gradually narrowing behind, 

 greylsh-slateeolour or light-brown : tentacles long, thick, and 

 nearly cylindi'ical ; upper ones covered with minute black 

 specks : foot slender. 



Shell globosely-pyramidal, rather thin, not glossy, horn- 

 colour or light-brown, marked transversely by about 30 plaits 

 of the epidermis, which rise in the middle of each whorl to a 

 sharp thorn-like point, as well as by smaller intermediate 

 folds, and striate spirally by close-set microscopic lines : 

 epidennis thick : ivhorls 4-4|, convex, gradually increasing in 

 size : periphery slightly and obtusely keeled : sjnre somewhat 

 compressed and blunt : suture deep : mouth rather large and 

 forming a deep arch : outer lip thickened with a white rib 

 and reflected in adult specimens : umbilicus narrow and small. 

 L. 0-1. B. 0-1. 



Yar. allida. Shell of a whitish colour. 



Habitat : Among dead leaves and moss in woods, 

 from Aberdeenshire to the Channel Isles. Variety from 

 Bath (Clark) . This species is one of our upper tertiary 

 fossils. Its foreign distribution extends from Finland 

 to Italy^ and even to the Azores. 



The animal walks with its shell erect, carrying it in 

 the most graceful manner. I have observed it feeding 

 on the Jungermannia platyphylla. Mr. Daniel informs 

 me that in Germany it travels high up into trees, par- 

 ticularly the alder, and that in the autumn it uses the 

 falling leaves as a locomotive to reach the ground. The 

 shell is an exquisitely beautiful object, especially when 

 it is fresh and encircled with its coronet of spines. This 

 character alone will serve to distinguish it from any 

 other British species of Helix. 



It is the H. spinulosa of Montagu. 



* Prickly. 



