to exclude the cold air. In this snug receptacle it 

 remains in a torpid state until the return of spring, 

 all animal functions being in the meantime sus- 

 pended. It then loosens and casts aside its winter 

 bonds and resumes its former life." B.C., vol. i. p. 179. 

 This species derives its name from a Greek word 

 which signifies an operculum, in reference to the 

 calcareous lid above alluded to, which is not, how- 

 ever, like a true operculum attached to the animal, 

 but a thick and rather convex plate which exactly 

 fits the aperture of the shell, and is cast aside at the 

 close of winter. The eggs of this species are round, 

 and nearly as large as a pea. They are deposited in 

 the earth, and the young are excluded after the lapse 

 of from twenty to forty-five days. 



Var. albida. Shell whitish or colourless, near Reigate (Brewer), 

 B.C. Charlbury near Banbury, Oxfordshire (D. Pidgeon), J.C., 

 vol. i. p. 56. I have never seen this variety in an immature state, 

 and am inclined to think that age has something to do with 

 the colour. 



4. H. ASPER'SA,* MULLER. PL. VII. 



Body oblong, dark brown, or dusky grey, speckled with white, 

 rou ;hly granulated ; tentacles long, slender, diverging at their 

 base, brownish, bulbs small ; foot rounded in front, and ending 

 in a point behind, margined with yellow ; lingual ribbon with 

 135 rows of 105 teeth = 14,175. 



Shell globose, somewhat thick and solid, of a dullish aspect, 

 almost opaque, yellowish with dark brown bands, of which 

 there are usually from four to five on the body whorl, and three 

 on the upper volutions ; these bands are more or less interrupted 

 and broken up by irregular white or yellowish markings ; epi- 

 dermis thick, closely indented, and coarsely wrinkled ; whorls 



* Besprinkled. 



