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488 APPENDIX—-HELIX PISANA. 
The eggs are perfectly spherical in form, about a millimetre in diameter, 
of a slightly violaceous white, with a mucilaginous investment, and though 
usually fifty or sixty in number, there may be occasionally as many as 
ninety, which are generally deposited in a little heap in one nest. When 
the deposition is completed, the snail covers the eggs with earth, forming 
a little mound, which to the experienced eye reveals the site of the nest. 
The eges hatch in about 12-17 days, according to temperature, but the 
tiny snails do not then disperse and abandon their nidus, but for a period 
congregate together and form a colony in its immediate vicinity. 
Food and Habits.—In Sicily, according to 'T. de Stefani, this species 
not only feeds upon a great variety of plants, but also devours the fruit 
of the Indian figs (Cuctus opuntia and C. tuna), which are regarded as 
quite inedible. 
The summer estivation is not carried out buried in the soil, or secreted 
in chinks and crevices, but attached to various erect supports, as dried 
stalks, tree trunks, ete., and always in positions fully exposed to the sun. 
The highest altitude attained by Helix pisana in France or in Corsica 
is said by Comm. Caziot not to exceed 2,500 feet. 
Enemies.—In Sicily, ‘I’. de Stefani has observed that the hedgehog, 
the crows, the magpies, and the owls prey upon this species, the owls 
especially showing a preference for and freely devouring them. Amongst 
the Coleoptera, the Carabids and Lumpyrids are also great enemies, while 
Testucella is said to devour the newly-hatched young. 
Geological Distribution.—Comm. Caziot records it as found rarely 
in the post-tertiary clays which form the sub-soil about Nice, but states 
that it has never been detected in the ‘“‘bone-beds” of Menton. 
_ Geographical Distribution.— Prof. Nobre records its occurrence on 
S. Thiago and Santo Antao, Cape Verde Islands, on the authority of M. 
Cessac. 
Variation.—''he Helix pisanw now so abundant near Paris have quite 
lost their fasciation, a circumstance which Dr. L. Germain quotes as 
illustrating the suggested rule that species introduced into a new locality 
tend to lose their normal banding. 
Var. globosior Shuttleworth (see p. 377). 
Helix pisana var. laghetensis Caziot, Moll. terr. et fluy. Monaco, 1910, p. 281, pl. 1, f. 4. 
The sub-var. laghetensis is described as shell very Z 
globose, conoid, spire much risen, solid, subopaque, ri 
milky white, very finely striate, six whorls, rapidly 
increasing in size; suture deep, the last subcarinate ; 
mouth rounded. 
Altitude 20 mill. ; diameter 22 mill. 
It is very close to the var. donnelli of Pallary (figured 
and described at p. 378), and is found on the coast of the Fic. 554.—H. pisana var. 
Alpes Maritimes from Menton, Monaco, to Théoule and laghetensis Caziot. _ Alpes 
to ‘Trayas, where it lives on porphyritie rock. Maritimes (after Cazoy): 
Var. minor Bourguignat (see p. 383). 
FRANCE. 
A var. minor, according to Comm. Caziot, is found in the Alpes Maritimes at 
Napoule, between Cannes and Théoule on the banks of the Var, near its mouth. 
TP AEY 
Tuscany—Found at Siena by Dr. Guebhard and recorded by Comm. Caziot. 
