ae 
376 HELIX PISANA. 
. . . e . . . 
Enemies.—Few precise observations are available on this subject, 
although their destruction by birds is frequently alluded to: Messrs. 
Baring and Grant have, however, recorded the finding of seven shells of 
this species in the crop of a Kestrel shot on the Salvages, and M. Raey- 
inaekers in Belgium found recognisable fragments of shell in the crop of 
a Wild Duck. 
Geological Distribution. — Pirtstocens.— Although Helir pisuna 
has not as yet been found in any Pleistocene deposits in this country, it 
has been recorded from the limestone beds on the sea-coast at Fouka near 
Koléah in Algeria by M. Bourguignat. 
Hotocenr.—In the Channel Isles, it has been recently discovered by 
_Mr. J. Sinel “in yellow clay or loess” beneath undisturbed soil, and un- 
doubted Neolithic relics, at a depth of from five to seven feet below the 
present land surface, on Green Island, an islet in St. Clement's Bay, Jersey. 
In France, it is recorded as rare by Abbé Dupuy from the rocks of Cardés a 
Lectoure, Gers, but some of the shells show more affinity with HZ. variabilis. 
From Sicily, the Marquis Monterosato reports the finding of the var. 
thalassophila in the beds on Monte Pellegrino near Palermo. 
In the Balearic Isles, the Rev. R. Ashington Bullen records the finding 
of specimens to a depth of eight feet in a hill-wash of holocene age at 
Porto Pi, near Palma, in the Island of Majorca. 
In Madeira, Baron de Paiva indicated it as rare in the fossiliferous 
strata of Canigal, but the Rev. Dr. Boog Watson, who visited the locality, 
found living specimens abundant there, and observed that dead and bleached 
shells may be picked up, filled with the calcareous sand of the fossiliferous 
bed, and having all the appearance of being truly fossil, but he never 
found any truly fossil specimens there. 
In the Canary Islands, Mr. J. Cosmo Melvill has holocene specimens 
of var. grasseti collected by Mr. 'l’. V. Wollaston on the Island of Fuerte- 
ventura. 
Variation.— Helix pisana is a species which has been happily described 
as diffusely polymorphic, its variations being so numerous that it has been 
split up or dismembered to form quite a number of varieties and so-called 
species, and received a multitude of names, the precise significance of many 
of them being now, however, almost unascertainable. 
Rossmiissler, who has studied the banding of this species, remarks that 
the five normal bands of the Pentateenia are rarely all present and per- 
fectly developed on the same specimens, but are always broken up or split 
into still more delicate bandlets. he first and second bands, so seldom 
seen in the //. virgata group, are, however, usually both present, but often 
represented by fleckings, and more rarely in the form of two to four thread- 
like bandlets. he third band is placed well above the periphery, and in 
normal specimens does not reach the suture on the penultimate whorl. 
The remaining bandlets belong to the fourth and fifth bands; the fourth 
band is usually broken up into five or six interrupted bandlets. ‘The 
fifth band, though occasionally split into two delicate bandlets, is commonly 
undivided, but much broken up and fringed, and seldom sharply defined. 
MM. Bourguignat, Servain, Letourneux, and others of the ‘“ Nouvelle 
Ecole” have given the species almost a generic significance by describing 
numbers of its modifications as of specific value, but none of the forms so 
