HELIX. 217 



above : umbilicus extremely large and open, exposing a con- 

 siderable part of the penultimate and preceding whorls and all 

 the interior of the spire. L. 0-25. B. 0-675. 



Yar. 1. alba, Charpentier. Shell milk-white. 



Var. 2. minor. Shell smaller. L. 0-2. B. 0*5. 



Var. 3. instabilis. Shell smaller, of a darker colour, and 

 sometimes streaked or spotted : sjnre more raised ; umbilicus 

 narrower. H. instabilis, (Ziegler) var. /3, L. Pfeiifer, Mon. Hel. 

 i. p. 165. 



Yar. 4. sinistrorsa. Shell having the sjnre reversed. 



Habitat : Dry heaths, downs, and sand-hills, on thistles 

 and other plants, in various parts of Great Britain, but 

 apparently not ranging further north than the Hebrides. 

 Var. 1 is also not uncommon, and is (according to 

 Gray) the H. obliterata of Hartmann, besides having five 

 other names. Var. 2. Kendal (J. G. J.). Var. 3. lona 

 (Lowe) ; Mull (Bedford) ; Connemara (J. G. J.). Var. 4. 

 Bridlington (Strickland). The shell is also inclined to 

 be occasionally scalariform. This species and several of 

 its varieties are widely diflPused over the Continent from 

 Cassel to Sicily; but it does not seem to inhabit the 

 extreme North of Europe, unless it is the same species 

 as that which Nilsson has described under the name of 

 H. ericetorum. The Swedish species has been considered 

 by many conchologists to be distinct, and it has been 

 named H. Nilssoniana by Beck, Malm, and other writers. 

 With the above exception, all the species comprised in 

 the present section appear to belong to what may be 

 termed a South-European type. 



This is a shy and inactive mollusk, withdrawing itself 

 into the shell on the slightest touch. The specific name 

 now borne by this very elegant shell was first given to it 

 by Lister, who observed that continued rains kill a great 

 number of them — a fact which I can corroborate. It 



