Our British snails

M. GILBERT & SON,
Ye Olde Boke Shoppe,
24, ABOVE Bar,
SOUTHAMPTON.

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REV. CANON Jw)’ HORSLEY

AUTHOR OF
‘SOME FOLK-LORE AND LEGENDS OF BIRDS,’

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LONER ON
SOCIETY FOR PROMOTING CHRISTIAN KNOWLEDGE
NORTHUMBERLAND AVENUE, W.C.
43, QUEEN VICTORIA STREET, E.C.
BRIGHTON: 129, NORTH STREET

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WILLIAM CLOWES AND SONS, LIMITED, °
LONDON AND BECCLES.

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LIBRARY

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Bish OF ILLUSTRATIONS

Canon Horsley in his study examining a rare variety of whelk
(var. Babylonica) from a stall in the Walworth Road.
Frontispiece.

fH. pomatia, half natural size

Dextral H. aspersa and H. pomatia
Love-darts of 7. pomatia, much magnified
77, nemoralis at rest on hawthorn

Names of parts of shell and of ges Unio, Limnea,
Vivipara, and Arion a Bois ee

Body of snail and of slug

Three specimens of Avion ater, showing tentacles, breathing
orifice, and slime gland

Testacella haliotidea

fielicella virgata at rest on thistle, natural size

Some of our smaller shells

Paludina contecta (two) and Limnea stagnalis on water-weeds
Neritina and Ancylus ...

Freshwater mussel breathing and eating ...

PAGE

OUR bRIrIshl SNARES

It has been said that a child’s education should
begin thirty years before its birth, since what he is,
or becomes, or does, depends largely upon what
his parents were, and not solely on what he learns
at home or in school, or from his companions
and surroundings.

But the principle of what is called ‘“ atavism ”’
shows us that the appearance, tastes, and charac-
ter of a child’s grandparents may reappear, even
more than those of his parents ; and that, there-
fore, his education begins sixty years before his
birth.

My education, viewing me as anaturalist, began
even earlier than that, for nearly all my ancestors
of whom I know anything more than their names
and abiding place were botanists or horticul-
turists, and I cannot recollect the time when I
was not an observer of nature and a collector of
the common objects of the field, the ditch, the
seashore, the wood, and the cliff. My father
died before I was four, and I have never had any
remembrance of his words or looks, yet I remember

8 | Our British Snails

his cutting down a tree in the shrubbery of his
Kentish vicarage garden which forked curiously
from the ground, and also of finding that handsome
fungus which is scarlet flecked with white. This
shows that the observation of the marvels and
beauties of God’s Green Bible, or Book of Nature,
began early in me. The habits of observation,
of comparison, and of method, are those which all
naturalists and collectors must have ; habits which
are of great value in other ways as well. Firstly,
one must have the seeing eye, and train it to notice
what many people do not. (Get and read the old
book, much read when I was young, called “‘ Eyes
and no Eyes.”) Secondly, one must lear (te
observe the difference (sometimes very small,
although important) between one object and others
of the same family. Every one knows a wild rose
by sight ; but nearly every one would be surprised
to hear that botanists make out twenty kinds of
English wild roses, to say nothing of varieties and
hybrids. In all departments of natural history
a magnifying glass, for the dissection of inward
parts, is necessary In many cases to separate
two kinds which look alike. And, thirdly, if
you want to make a collection, whether of dried
plants, of insects, of shells, or of anything else,
you must cultivate ways of order and method
and neatness in the arrangement of your collection.
And then your increased powers of observation,
of comparison, and of method will stand you,

Our British Snails 9

and others, in good stead in higher matters of
thought and action, and the virtues of Prudence,
Justice, Temperance, and Fortitude will all
increase in you as you learn more about what is in
man, what man should be, and how men should
be treated. Let us take Fortitude for example.
I have known boys who collected one kind of
thing eagerly for awhile, but soon got tired of
it, and generally had little power of “‘ sticking ”’
to anything. On the other hand, 1 was once
admiring the magnificent collection of shells owned
by a middle-aged doctor, and asked him, “* When
did you begin to collect?’ ‘“‘ When I was
seven,’ was his answer. I should expect to find
more Fortitude in that doctor’s character than
in that of a boy who collected “‘all things in
turn and nothing long.”’

Yet I myself was middle-aged before I felt
disgusted with myself, when gazing on a lad’s col-
lection of British land shells, that I should so long
have been groping in hedges and ditches, and
yet never have noticed the variety and the beauty
of members of the snail family. (That lad, by
the bye, is now a Professor in an American
University, and a great authority on shells and
other matters.) Since then I have gathered a
complete collection of the British land and fresh-
water shells, and a very large and valuable one
of the Helicodea—t.e. the family to which the
common or garden snail belongs—of every

10 Our British Snails

country in the world; and have been President
of the Conchological Society of Great Britain
and Ireland.

I am now, therefore, writing about our British
Jand shells, “‘slugs and snails’? in common
speech, with the hope that it may add a new
interest to the country walks of lads and lasses.

I could show you a wall-case I made for a school.
It contains specimens of all the British land
‘shells with the exception of the slugs, which
(with the exception of one of which I shall speak
in its place) have no external or covering shell,
although a small sort of shell, or at any rate
some chalky grains, is found inside most of them.
You would see that some are as small as a pin’s
head although full grown, and they would require
a magnifying glass to distinguish one from the
other. The largest is Helix pomatia (figured on
pp. 11 and 12), which often goes by the name of
“the edible snail.’”” All snails are edible and nu-
tritious ; but this is the one cultivated in snail
farms and sold as food abroad. Sometimes it
is called ‘‘the Roman snail,” from an idea, pro-
bably wrong, that it was introduced by Czsar’s
soldiers, although as a matter of fact it is unknown
in South Italy. Sometimes also it is called ‘‘the
apple snail,” partly because it is as large as a
middle-sized apple, and partly because people
thought the name pomatia came from the Latin
pomum, ‘‘an apple,’’ whereas it really comes from

Our British Snails Il

the Greek wiua. This word means a lid, or
closing arrangement, and this mollusc makes a
hard front door for itself when it hibernates, 7.e.
suspends active life and buries itself in the
winter.

It is much to be regretted that in most cases

H. pomatia, half natural size.

scientific names fail to give much information to
the young student, and in some cases they give
none atall. The first or generic name is supposed
to be formed from Greek, the second, or specific,
from the Latin, but there are some hybrids and
many mere ‘‘nonsensenames’’ topuzzle beginners.
Thus the slug Limax gets its name from limus,
“mud’”’; but ascientist, who ought to have known

12 Our British Snails

better, when wanting a name for another kind
of slug, transposed the initial letters and made
Milax! Vitrina is a sensible and descriptive.
name, the Latin for glassy, given to a shell like
thin glass ; but the Greek Arion recalls either a
certain musician or a certain swift steed, neither
of whom naturally suggests a slug. For Balea
at least four derivations have been suggested—
none of them probable. Two facts concerning the
‘life or appearance of a mollusc we should learn
from its two names, but this is not the case with
Agriolimax agrestis, which is by interpretation
“the field slug inhabiting fields.”” Nor are we
helped by the specific name virgata or striped
when so many land shells are striped or banded,
and still less by terrestris for one land shell When
all land shells are terrestrial.

You would note, however, in this wall-case
that the species are not many (a good many of
the specimens are varieties, not separate species),
and that, therefore, one can collect with the hope
of speedily forming a complete collection without
that inevitable absence of finality found when
one collects postage stamps, or, still more, picture
postcards, of which one might secure thousands,
only to find that fresh thousands were brought
out next year. Here, however, is no impossible
ideal of perfection. There are but eighty-
two land and forty-five freshwater shells in
Britain.

Our Brittsh Snails 13

Let us imagine we are starting for an afternoon
snailing near London. Which way? To Ox-
shott ? To Caterham? To the latter for choice,
since it is on the chalk, whereas the former is

Dextral H. aspersa and H. pomatia. The right-hand
shell at the bottom shows the winter epiphragm of
H. pomatia.

on the sand. Snails require lime to make shells,
and only on chalk or limestone will you find an
abundance. Here, too, as at Box Hill, we shall

14 Our British Snails

find the big Helix pomatia, only found in a few
English counties, and very local there. If we
were very fortunate, we might find a sinistral,
or “‘ left-handed ” specimen. In the case of the
pomatia on the right hand there is shown the
thick epiphragm which the mantle secretes before
the mollusc hibernates. It hardens on exposure
to the air like plaster-of-paris ; but is not a true
operculum, for that is a constant possession of
the shells which have it. Opercula are mainly
found in marine or fluviatile shells, and may be
either horny (like the winkle) or stony. Amongst
our British land shells Cyclostoma elegans and
Acicula lineata alone have true opercula, though
others form some thin epiphragm for the exclusion
of cold air and enemies when they hibernate.
Most shells grow to the right, and a freak which
does the contrary is so rare that of the millions
of the common H. virgata that I have seen and
handled, only one delighted me with its left-
handedness. If it is early summer (nearly all
snails hide, burrow, and sleep during the winter),
look about on the grass for some half-chalky,
half-stony shields, which are the winter front
doors of H. pomatia, now discarded; while
sharper eyes might even descry the flinty little
darts with which they have been love-making.
The illustration on p. 15 shows three of these
darts, much magnified. Only the most highly
developed Helices possess these courting weapons,

Our British Snails 15

not unlike bayonets in form, sometimes rounded
and smooth, and sometimes with two or even
four lateral blades, so that the section of the dart
of H. pomatia is in the form of a Greek cross.
Not many British shells have these darts, but in

Love-darts of H. pomatia, much magnified.

one case their study is useful, since H. nemoralis
and H. hortensis, though so closely allied that
early conchologists considered them to be of the
same species, have darts remarkably distinct one

16 Our British Snails

from the other, so that they become a court of
final appeal if from outward appearance it is
difficult to distinguish, say, a white-mouthed
nemoralis from a dark-mouthed hortensts.

Whenever you see a Stone, a brick, a branch
of dead wood, or even an old boot or a piece
of newspaper in the hedge or on the grass, turn
it over, for many of the smaller shells are thus
found, and “‘ leave no stone unturned ”’ is emi-
-nently a motto for the conchologist. Some of
the shells will be tiny, and must be studied under
a magnifying glass—which all naturalists should
always have in their pockets—or even under
a miscroscope at home, in order to discover, not
only their beauty of marking or sculpture, but
even to what species they belong.

When you see a man sweeping herbage with
a net, or beating hedges and shrubs over an
inverted umbrella, he is probably an entomolo-
gist in search of caterpillars or beetles ; but the
same methods will often reward the snail-hunter.

Especially in the hedges will you find the two
allied species Helix (Cepea) nemoralis and hovtensts,
to which the attention of beginners should frst
be directed, inasmuch as they are so common, so
beautiful, and so varying both in colour and the
number of the chocolate bands they usually bear.
See the illustration of some of these at rest on
hawthorn, p. 17. Canary-yellow, flesh-colour,
chocolate, and almost white, are the prevailing

Our British Snails 17

ground-colours. Five is the normal number of
bands on the largest or body-whorl, although
sometimes all run into one, and often one, some,

E

H. nemoralis at rest on hawthorn,

or all are wanting. Where only one band is
found—throughout the Helicide—it is usually
that on the periphery or middle of the whorl,
and a shell in which this band is wanting, while
others are found, is a rarity. People are usually

astonished, on seeing a good series of the colour
B

18 Our British Snails

and variations of these two shells, how they vie
with those of warmer regions.

Next search trunks of trees, and especially
the smooth boles of the beeches. The rough
bark of the elm or oak is not congenial to slugs
or snails. Where trees are moss-covered at
their foot, or walls at their top,many of the smaller
shells may be expected ; while handfuls of dead
leaves may be shaken over something white,
- or taken home in a large bag to be treated there.
Hurdles leaning against a hedge are often found
to bear a good crop of snails. Damp places
must be sought in dry weather; but a rainy
day, that troubles some kinds of naturalists, sends
the conchologist forth rejoicing, especially if
a warm evening follows a wet day. A night
search with a lantern will often be profitable.
Where they will be undisturbed, traps may be set,
such as flat pieces of wood (the older the better),
or cardboard, lying on the grass ; while most of
those species that belong to the group which
seems to prefer the sun, e.g. H. ztala, virgata, etc.,
are fond of a newspaper for food rather than for
shelter.

During the hibernating season, which extends
from November to April, we turn rather to ditches
than to hedges, and, armed with a perforated
scoop at the end of a long stick, we dredge among
the water-weeds, or sift, like gold-washers, the
sand or mud in ditches, ponds, and backwaters

Our British Snails 19

of rivers. Here we are introduced to the great
bivalve family which is unknown on land, and
our trophies range from the freshwater mussels,
as large as our hand, to others hardly larger than
a pim’s head .- These must be sought at the
bottom ; but on the weeds, or on the bottom, will
be found not a few species of gasteropods or
univalves, some of which we may have noticed
in a freshwater aquarium. These, of course, are
closely connected with the land shells, which
the bivalves arenot. They can be brought home
alive in a tin box with a little moss, whereas
for the land shells a calico bag with a little foliage
therein is best. In both cases some small glass
tubes with corks should be brought in a tin box
in order to keep safely and separately the tinier
kinds. You can often discover what small shells
inhabit a particular ditch or pond by noticing
the cases of caddis-worms, some of which are
formed almost entirely of shells instead of vege-
table fragments.

Using the precious gift of PReatia we have
found our shells; at home we exercise the other
gifts of comparison and order, in the preparation
and arrangement of our collection. A dash
of quite boiling water kills instantaneously any
molluscs whose shells we want to preserve,
and then the body is extracted after the fashion

observed with regard to winkles at tea. Be
careful to get out all the body of the animal, and

20 Our British Snails

then it is well to wash out any slime or particles
by directing a fine but strong jet of cold water
into the shell. This can be done by holding
your thumb nearly over the mouth of a water-
tap, while the shell is held in the left hand. Only
adult shells should usually be taken, and those
which are weather-worn or bleached should be
neglected. In most the lip; or opening; of the
Shell will be hard if adult, and membranous if
young; but experience alone will enable you
to discriminate, especially where the young oi
one species is like the adult of another.

Get into the way of carrying a note-book
with you to record not only what shells, or
varieties of a species, are found in any particular
spot, but also anything you observe as to the
habits or peculiarities of the objects of your
search. Notes as to protective colouring or
mimicry ; the influences of a wet or a dry season
on the relative thickness of shells ; the difference
in size caused by abundance or scarcity of diet ;
what plants are preferred and what avoided
as food by particular helices,—are some of the
points of interest, apart from the earliest and
latest dates at which certain species are abroad
and active.

If you possess, or borrow, a microscope, many
new wonders and fresh lines of inquiry will
open out. I know one professor who devotes
himself to the study of the teeth of molluscs.

Our British Snails 21

A snail may possess over twenty thousand tiny
Himty teeth set on a ribbon so as to make a
mowing-machine for the vegetable matter on
which it feeds. Withits aid also you might study
the life-history of a mollusc from the egg onwards,
and be able to determine by minute anatomical
points whether two molluscs were of the same
species or not—a matter in which the shape or
appearance of the shell is not always a safe guide.

Here, then, is a new hobby for some of my
readers, or, at any rate, a fresh source of interest
when they are in the country. If any collector
lives near you, I am sure he or she would be
delighted to have your company during an
expedition, and you would learn more by sight
and hearing than by reading. If, however,
you must fall back upon a book, get The Collector’s
Manual by L. E. Adams, published by Taylor
Bros., Leeds. This is invaluable both to the
beginner and to the owner of a good collection.

From this I borrow by leave the plate on
pee 22. which wily enable, the beginner to
understand from the first certain names of
paris of the shell or the body of the bivalve,
univalve, or slug which otherwise might not be
clear. The “‘ muscular scars ’’ are indents in the
shell which mark where the muscles were fixed
whose function was to bring close together the
two valves of the shell when it has need to exclude
air or enemies.

Cardinal. toath. pt GOMeLTEL
[ hinge) =

Muscuule 2° > Musciulgr Sear
Cai “Right- :

VALVe

Me sli QaMent

figs - :
LUG?
rT
ft 1 fae
COUNT ELLD

Ubi licuS: =

Tentacles

CMa

RESALE al Lary

Or fib

Names of parts of shell and of body. Unio, Limnea, Vivipara,
and Arion.

Our British Snails 2

The figures of the snail and the slug below
are introduced to give further knowledge of the
soft parts. Bis the body, soft and with a surface
generally wrinkled or covered with small tubercles.
F is the foot or muscular pad which forms the
foot by the wavelike contractions of which it
moves. H is the head, bearing the tentacles T,

Body of snail and of slug.

and T,, of which the upper pair have the eyes, E.
The mantle, M, makes the shell by secreting lime,
etc. In it is the breathing orifice, BO, obvious
in the slug, but in the snail nearly hidden by the
shell. L in the snail is the spiral part, the liver,
and it occupies a large part of the shell.

Without going into details of classification
and anatomy, which would only deter or puzzle
a beginner, let me take two typical molluscs

24 Our British Snails

of those which we shall find in England, the
common garden snail Helix aspersa, and a fresh-
water mussel, Unio margaritifer, and see where
they come in the scale of creation and what are
their powers and peculiarities.

Molluscs (mollis esca, soft food—boneless crea-
tures) are below the aristocracy of the vertebrates
or backboned creatures, and so they come just
below the Fishes, but above the Insects. They
are divided into those possessing a head and
those possessing no head (although with some sort
of a brain or organ of sense), the snail being of
the former class and the mussel of the latter.
The former are univalves and the latter bi-
valves having two shells for protection. The
latter also are restricted to life in water,
whereas the former are found both on land and
in water, ¢.g. the snail and the whelk, although for
ages probably no molluscs were air-breathing
land dwellers. In the class of Cephala, to which
our snail belongs, there is the sub-class of Gastero-
poda, or stomach-footed, because on the ventral
side of the body a sole-like disc or foot exists,
by the wave-like expansions and contractions
of which the animal progresses.

In this sub-class there is a division accord-
ing to their having or not having an operculum,
or means of closing and protecting the orifice
of the shell. Most gasteropods which live in
water have this; most which live on land (only

Our British Snails 25

two exceptions in British molluscs) have not.
Here again we must trace our snail down to the
sub-order of Pulmonata, or lung or air-sac breathers
as distinct from its sisters which inhabit water
and breathe by gills. This sub-order is again
divided into various families, Arion, Limax,
Testacella, Vitrina, Zonites, Helix, etc., and
Helix again is divided into various genera,
of which Helix is one, and even this is sub-
divided into sub-genera, Patula, Punctum, Acan-
thinula, Vallonia, Chilotrema, §Gonostoma,
Pomatia, Tachea, etc., and to the sub-genus
Pomatia our garden snail as well as the ‘‘ Roman
snail ’’ belongs. Looking backwards we, therefore,
place our friend as the species aspersa, of the
sub-genus Pomatia, of the genus Helix, of the
family Helicide, of the sub-order Pulmonata,
of the order [noperculata, of the sub-class Gastero-
poda, of the class Cephala, of the sub-kingdom
of Mollusca, of the kingdom Invertebrata or
backboneless animals.

It belongs by origin not to the earliest form
of snail, but to the most highly organized group
in the world, especially characteristic of the
European region, and possessing in their superi-
ority the power to colonize and_ dispossess
the criginal native snails of other lands. The
shell is globular in form with five whorls (the
Greek word ‘‘helix”’ means a coil), each usually
marked with five bands of pigment. It is mainly

26 Our British Snails

a vegetarian, and by habit a lover of the twilight
and of moisture. With the exception of JH.
pomatia it is the largest of our native shells, and
is too common to satisfy gardeners. A powerful
animal of its kind, it can travel a yard in twelve
minutes, or at the rate of a mile in a fortnight,
can bear or draw on level ground a weight fifty
times its own. It breathes about four times a
minute, and its heart-beat varies from sixty to
eighty per minute according to temperature,
orits activity. It takes its winter rest in clusters,
closing its mouth with a membranous film, while
if the cold increases it shrinks farther into its
shell and makes more epiphragms or film curtains
to keep out the cold. Not only on the Continent,
but in several parts of England, notably about
Bath and Bristol, it is sought, sold, and used
for food, and in Belgium it is said to be
preferred to the larger and more firm-fleshed
H. pomatia. The eggs, from forty to a hundred,
are laid in the earth and hatched in from a fort-
night to a month, according to the weather. I
had observed them as a boy, and used to call
tapioca pudding “snail’s egg pudding.” In
the year of their hatching they attain but half
their proper size, but after hibernation they eat
voraciously and grow rapidly, so as to attain
full. size in a little more thana jyear, ies:
die in their second hibernation (if not destroyed
by their many enemies, gardeners, collectors,

Our British Snails 27

rats, rabbits, ducks, thrushes, and _ beetles) ;
but when kept and protected for observation
they have achieved the great age of even ten
years.

They have a great power of ‘‘ homing ’”’ like
pigeons, however far (for them) is their journey
after favourite food. The shme-marked journeys
or feeding tracks of this species (and still more
of slugs) afford matter of great interest. As
to sight the two eyes are the dark specks on
the tip of the upper pair of “horns,” but the
range of vision is very short indeed, and the
difference between light and approaching dark-
ness is all that some seem able to perceive. The
organs of hearing are two small sacs filled with
fluid in which are some calcareous grains. They
hear little which is audible to human ears, and
if not altogether deaf they are dumb as far as
we can hear. The power of taste they possess,
as is shown by the preference of some foods to
others. The sense of touch is acute and resides
in all parts of the soft and moist external skin,
and especially in the upper tentacles or horns in
the Helicid@a. Jaws they have with which to
seize and to bite off food, and in H. asfersa and
others these bear teeth, but the chief work is
done by a sort of toothed tongue, the radula,
which rasps off particles of food with a side to side
motion of the head as the animal advances.
Our aspersa has 12,615 teeth on this ribbon,

28 Our British Snails

contained in 145 transverse rows. The organs
of digestion are complex and practically much
the same as our own. Little vegetation would
be left in nature had not, on the one hand, snails
been kept down by many enemies as well as by
their need of hibernation and their short life ;
while on the other by numerous devices in the
course of ages many plants have protected
themselves against the moving machine of a
onal’) “mouth. Cultivated plants, which
generally lose their natural protections, have to
be guarded by human guards or gardeners.
Some plants defend themselves by prickles or
hairs, some by hardening themselves with lime
or flint, some by bitter or acrid juices. A heart of
two chambers, veins, arteries, and blood our snail
possesses, and, like man, the old snail has a slower
pulse than the young one, and in both exercise
increases the pulse rate and also warmth.
Breathing is accomplished by a single chamber
or air-cell, but also through the skin. As in the
case of plants, some kinds are male and female
separately, and as some have both powers and
products in the same plant, so also is it with
mollusca. H. aspersa and most Gasteropoda
are of the latter kind.

Having now taken H. aspersa as the repre-
sentative of our univalves, let us take the “ Pearl
Mussel ’’—Unio margaritifer—as that of our bi-
valves, all of which live in the water, whereas

Our British Snails 29

of univalves some are “land snails’’ and some
Mowater snails,” “Li;wouldssay ot-itselis “) am
a species of the genus Unio (u20, a pearl), which
belongs to the family Unionide, which belongs
to the sub-order Isomya (.e. having muscles
of equal power to close the two valves of the shell),
which belongs to the order Lamellibranchiata
(i.e. having gills arranged in leaf-like fashion),
which belongs to the sub-class Pelecypoda (1.e.
having a foot somewhat of an axe-shape), which
belongs to the class Acephala (headless), which
is the second of the two chief classes into which
Mollusca are divided.

‘“T differ from the Gasteropoda (whether they
be terrestrial or aquatic) in that I and my near
relations are exclusively aquatic and of asedentary
life, which makes the protection of two encom-
passing shells necessary. These shells are secreted
by my mantle lobes, and are united by a hgament
which tends to make the valves ‘gape’ for
water and food and by two contracting muscles
which close them in danger. I have a degenerate
brain and no eyes. My mouth has neither jaw
nor teeth, but possesses nervous lips covered
with cilia, the vibration of which carries food-
laden water to my mouth. My foot, when pro-
truded, is seen as a large muscular appendage,
and, by alternately expanding and contracting,
it enables me to burrow or plough through mud
or even sand, wand so disturb the minute

30 Our British Snails

organisms on which I feed. I can thus travel
fifteen feet a day, or about a mile in a year.

‘“T have no eyes, but distinguish well between
light and shade by means of the surface of my
body when exposed. I breathe, that is, get oxygen
from the water, by means of gill-plates. As
regards other internal organs, I differ not much
from H. aspersa, but I am either male or female.
Outside I am black and uncomely; but within
I am pearly-white, and but for my power of
forming pearls round an irritating grain of sand
the civilization of England would have come
to pass later than it did, for it was the report
of my pearls which brought Cesar to Britain.”

Now let us enumerate the species of land and
freshwater shells to be found, (all but two) in
England, and most of them in Ireland or Scotland.

Arion ater is a large (3 to 5 inches) and common
slug, usually black (whence its name ater), but
also red, brown, or white. In some varieties
the foot-fringe is orange. When irritated it
contracts into a hemispherical lump. A few
chalky granules under the mantle are the repre-
sentatives of a shell. See the illustration of three
specimens on p. 31. That hole in the mantle is the
breathing orifice, and its forward position is a
_characteristic of the group Avion. The body of
slugs is kept moist by a constant exuding of slime
from a gland in the tail.

Our British Snails 31

Arion subfuscus (t.e. somewhat tawny). Smaller

Three specimens of Avion ater, showing
tentacles, breathing orifice, and slime
gland.

(2 to 3 inches) than A. ater, grey or yellowish,

32 Our British Snails

with usually a dark stripe on each side. Foot-
sole white, and its fringe white with dark cross
streaks. Never very abundant.

Arion minimus.—The smallest Arion: not an
inch long. Grey or yellowish. Feeds on fungi.
Body wrinkled with microscopic spikes. Common.
The young of A. ater might be mistaken for it.

Arion hortensis.—Grey with purple side bands.
Foot-sole yellow. 1to1jinchinlength. Generally
found in gardens, as its name indicates.

Arion circumscriptus.—Very common in fields.
A dark band down the back, foot-sole white.
Very “‘ sluggish.”’

Geomalacus maculosus (t.e. the spotted earth-
mollusc).— Only found in south-west Ireland.
Probably a relic of the prehistoric time when
Treland was joined to Portugal and Spain. Has
a solid chalky shell beneath the shield. Blackish
with oval yellow spots. Feeds on lichens.

Amalia gagates (gagates is Greek for “jet ”’).—
Dark lead colour. Foot-sole white. Length 2$
inches. Local, and mainly near sea.

Amalia Sowerbyi.—Brown, speckled with black.
Foot-sole yellowish. Length 23 inches. Local.
Shell often very thick.

Limax maximus.—Length 4 to 6 inches. Grey
with two dark lateral bands. Often found in
cellars.

Limax cinereo-niger.—Ashy-black. Very like
L. maximus, but with a sharp keel, and the sole

Our British Snails 33

paler m the, middle; than. at the sides. Less
nocturnal and less fond of houses ; chiefly found
in forests on hills. Local, and not common.

Limax flavus—Yellow, with a faint dark net-
work of markings. Tentacles blue. Sole cream.
Length 4 inches. Only found in cellars and near
houses.

Limax marginatus.—Semi-transparent. Grey,
with two dark bands on each side. Foot-sole
with a dark line down the middle. Shell solid,
omemyascube: “Weeneth 3 inches. Pond of tree
climbing.

Limax tenellus——Yellow. Tentacles — black.
Mucus yellow. Found in woods. Lives on fungi.
Rare.

Agrniolimax agrestis——The common field slug.
Swarms everywhere. Its milk-white slime is
characteristic. Very variable in colour and
markings.

Agriolimax levis—Slender. All chocolate
brown. Length ? inch. Shell may be seen
through the mantle. Active. Our smallest slug.
Usually found near ditches.

It may be useful here to give the chief differences
between the genera Arion, Amalia, Limax, and
Agriolimax. The shield in the first two is
granulated, in the other concentrically striated.
The breathing orifice in Arion is in front of the
centre of the mantle margin; in the others

fe

34 Our British Snails

behind. The shell is distinctly formed in all but
Arion, in which.it is absent or represented by a
few granules. Arion has no dorsal keel. Amalia
has one all down the back. In Limax and Agrio-
limax it is confined to the caudal part. Other
differences are only discovered by dissection.

One may also here note that to preserve slugs
is difficult, and the best plan is to have a coloured
drawing made of them when extended. Other-
wise they may be drowned in cold water, cleaned
of slime with a soft brush, and then preserved
in glass tubes with diluted formalin or alcohol.
Or, after drowning, they may be skinned and the
skins dried on a card and varnished. Note also
that most slugs have many variations in colour
and markings.

Testacella haliotidea.—This genus of slugs forms
a link between the naked slugs with rudimentary
shells within, and the snails which live within
their shells. The name Testacella, or little
shell, was given by Cuvier in 1800, because this
slug has asmall shell at the end of the tail. Halio-
tidea means having a shell in the form of the
marine shell Haliotis, the meaning of which again
is the ear-shaped seashell, often called ‘‘ Venus’
Ear.” It is subterranean in habit, and lives on
worms. It should be looked for on the surface
on damp nights, or is found when digging. Its
length is 3 inches at most. Pale yellow in colour.
See the illustration on page 35.

Our British Snails a5

Testacella scutulum (a little shield).—Not so
common as the former species, and differing chiefly
in anatomy.

Testacella Mauget.—First found at Tenerife by
M. Mauge. Reaches 4 inches in length. Deep
brown in colour. Shell larger. Rarer and more
western in habitat than the other species.

i eee

Testacella haliotidea.

Vitrina fpellucida——The Vitrinas in several
ways afford a connecting link between the slugs
and snails, having the same tooth-formation and
mantie as the former, while the shell cannot
contain the whole body. As the name indicates,
the shell is like a bubble of clear greenish glass
and very delicate. It is small, and found in damp
places, coming out mostly at night. Omnivorous,
it is often found feeding on dead worms, and,

36 Our British Snails

unlike nearly all our earth molluscs, can be
found abroad in winter.

Vitrea (Polita) lucida.—This is the largest
oi our British Hyaliniz, which are difficult to
distinguish. The body of this species is cobalt
blue, the apex of the shell is flat, ifs colous
opaque, and the last whorl more expanded than
in others. All belong to the sub-genus Polita, and
have polished or glossy shells. All love shade
and moisture, and should be sought under stones
or wood or in moss. They only come out by day
when it is wet, a habit they may have acquired
from their being a favourite food of birds, 416
having been found in the crop of one nestling
Stockdove ; while various flies are very de-
structive to them. This species prefers animal
food, and is more gregarious than others. Not
common.

Vitrea (Polita) cellarvia.—The next largest species
is the most common of all. It is fond of cellars
(whence its name), and I found it under the stone
lid of a manhole in the drain of S. Peter’s
Rectory, Walworth—the only shell left in that
part of London. It resembles the previous
species, but is smaller and has a broader and deeper
suture between the whorls, while the foot-sole
is paler than the body.

Vitrea (Polita) Rogerst.—Local. Found in dense
woods. It is much like both H. cellaria and
H. alaria, and all three smell’ of ~ganhe;

Our British Snails a7

but the last is much smaller than the others.
The tentacles in the first are long, and in the
third short; while in Rogersz the upper pair
are long and the lower very short. It is also the
most glossy of all. If put in a box with other
small shells it will clean them by cannibalism.

Vitrea (Polita) alliaria, 1.e. smelling of garlic.—
Often confused by quite good conchologists with
the preceding species, but the bedy 1s much darker,
and the shell smaller and less white below than
either cellaria or helvetica. The always present
smell is said to protect it from ants. Common,
but local, and often a pest in greenhouses and
ferneries.

Vitrea (Poltta) nitidula——Common. Less glossy.
Marked expansion of the last whorl as it nears
the mouth.

Vitrea (Polita) pura.—Like mitidula but smaller,
and edge of mantle white instead of dark. More
common in the north. Shell thin and dull white.

Vitrea (Polita) vadiatula—Never abundant.
Striations on shell give it a radiated appearance
when magnified. Animal nearly black.

Vitrea crystallina.—The smallest of the genus.
Shell transparent, pearly white. Umbilicus (2.e.
the opening in the centre of the underside
showing the whorls) very narrow. Subterranean
in habit. Whorls, four; whereas H. pura has
five ; also more compressed.

Euconulus fulvus.—Distinctively pyramidal in

38 Our British Snails

shape. Small. Brown. Common under rotten
branches and moss in woods. Hardly hibernates.

Zonitoides nitidus —Chocolate-brown, with no
white round the umbilicus (as has H. nitudula).
Larger than, but not unlike, H. radiatula. Gre-
garious. Chiefly found by water; also in damp
hothouses. Amphibious.

Zontoides excavatus.—Its broad and deep
umbilicus is quite distinctive. Mainly British.
Dislikes lime, and is most plentiful on the coal
measures.

We come now to the Helicide family and its”
genus Helix, in which there are various sub-genera
of which the name is given in brackets. The
shell in this genus can wholly contain the body ;
the tentacles are always four; the shell conical,
and rarely with a depressed spire. The word
“helix ’’ is Greek, and means a coil.

Helix (Gonyodiscus) rotundata.—Very common
under stones, moss, etc. -Circular, flat, with a
large open umbilicus. Horn colour with brown
markings.

H. (Pyramidula) rupestris, 1.e. inhabiting rocks.
—Small. Gregarious. Dark brown. Mainly on
exposed dry walls and cliffs.

H. (Punctum) pygmeum.—Very small. Yel-
lowish brown and glossy shell. Mainly on moist
dead leaves. Not unlike H. rupestris except as
to habitat.

H. (Acanthinula) lamellata—Small. Horn-

Our British Snails 39

colour. Epidermis raised into lamelle or ridges
in the line of growth. Mainly northern. Fre-
quents dead leaves, especially beech and holly.

H. (Acanthinula) aculeata—More common than
the former; which it resembles in habitat.
Differs chiefly by the ridges being produced into
spines.

H. (Vallonia) pulchella—Tiny. White. Mouth
trumpet-shaped. Umbilicus wide. Under stones
and at the roots of grass. Its variety costata
(which some make a separate species) is strongly
ribbed.

H. (Helicigona) lapicida.—Circular, flattened,
dark brown, strong white reflected rim to mouth.
Large umbilicus. Marked keel, which distin-
guishes it from all other British land shells.
Chiefly on chalk soils. Often on beech tree
trunks.

H. (Gonostoma) obvoluta.—Common abroad, but
confined in England to a few spots in Sussex and
Hants. Circular, flat above, mouth triangular,
with a strong pinkish-white rim with three
denticles.

H. (Pomatia) pomatia.—Described earlier.
Found in Hants, Sussex, Kent, Surrey, Oxford,
Gloucester, and Bedfordshire; but very local.
Elsewhere it may well be an escape from captivity,
or the remains of an attempt (always unsuccessful)
to establish a colony. Boxhill and Caterham
are two good localities for Londoners. In Kent

40 Our British Snails

it has two centres, Charing and Shoreham with
their contiguous: parishes, but there is a great
gap between them, and it is absent from places
on the same chalk ridge which are identical in
soil and vegetation.

H. (Cryptomphalus) aspersa.—The sub-generic
name means that the umbilicus is hidden in
adult shells by a fold of the pillar lip ; the specific
name means sprinkled (with brown blotches) ;
but it may be a slip“ot the pen; for aspera, on
rough, from the rough shagreening of its surface.
Five banded, hike so many of the Helicide, but
usually the second and third band unite. No
umbilicus. The variety exalbida (chiefly found
in Kent and the West) is straw colour and some-
what transparent. Commonly sold for food
on the Continent as well as Jomatia, which is
cultivated in “snail-farms,’’ but not native m
Germany or Switzerland, and in France chiefly
found in the coast departments. Insipid; but
as nourishing as calf’s-foot jelly. Fond of gardens
(whence its common name), but not of gardeners.
As most animals are marvellously gifted with a
knowledge of what food to eat and what to avoid,
it is curious that aspersa will eat voraciously the
leaves of the spindle-tree, though this soon poisons
them. It is said also that they share with cows
and horses the ignorance that the leaves of the
yew should be avoided on pain of sickness or
even of death.

Our British Snails AI

H. (Cepe@a) nemoralis.—As already stated, this
is the most brilliantly and variously coloured
and diversely banded of all our English land
shells with the exception of its very close con-
nection H. (Lachea) hortensis. It is happily
very common, and so the attention of beginners
should first be directed to this. Thrushes and
mice are its great enemies, the former smashing
it on some stone which may be found sur-
rounded by the broken shells. The ‘‘ mouth”
or peristome is normally black, the shell larger
and stouter than fortensis, in which the mouth
is white. When a white-mouthed nemoralis or
dark-mouthed hortensis (both rare) is found, the
shape of the internal flinty dart at once distin-
guishes them. In some places both live together :
in most one is found and not the other. Nemoralis
is fond of sand-hills by the coast, but is chiefly
a hedge-snail, and the edges of main roads are
preferred because of the greater variety of food,
because the traffic scares away their bird enemies,
and because the dust gives them abundance of
already prepared material for their shells. When,
however, the collector comes to a wayside cottage
where fowls are kept he need not waste his time
in looking for snails in the neighbouring hedge.
The more the chicken industry extends and the
more the Bird Protection Acts operates, the
worse it is for collectors of snails. The banding
is probably protective, as in the case of the

42 Our British Snails

tiger and the zebra, and renders the shell less
visible.

Helix (Cepea) hortensis—Rarely found in
gardens in spite of its specific name. A hedge-
snail. White forms not uncommon, though al-
most unknown in nemoralis. Though the weaker
form, the coalescence of the five bands into one
broad one is more common here than in nemoralis.
Also the variety with only one band, and that
on the periphery, is very common in nemoralis
and rare in hortensts. It is more dependent on
shade and moisture than its congener. Smells
of garlic when immersed in boiling water to be
killed. Hortensts is a more northern, and nemo-
valis a more southern, shell by origin and distri-
bution. There are 89 possible band variations
in any normally five-banded shell, and all have
been noted in the case of nemoralis, but in hor-
tensts only 61. They are distinguished, for
purposes of record and exchange, by numbers.
Thus the type is 12345, the usual one-banded
variety 00300, the common coalescence of the
second and third band is 12345, and when all
bands unite Y2345. The unicolourous or bandless
variations would be 00000.

H. (Arianta) arbustorum.—Local. Usually
found in hedges and by ditches on chalk and
limestone. Shell globose, brown or yellow, with
a check or willow leaf pattern, and a single dark
band on the periphery. Lip strong and white.

Our British Snails 43

Animal usually nearly black. Very fond of
moisture. Anatomically related to A. lapicida,
but no external resemblance.

Helix (Theba) cantiana.—First observed in Kent
(where it is especially fine and abundant); whence
its specific name, but generally dispersed in
South and East England. A dull, creamy white
shell with a pink tinge, sometimes becoming
partially or wholly reddish.

Helix (Theba) cartusiana (first noticed near
a Carthusian monastery). Much _ resembles
cantiana, but is much smaller and more smooth.
Chiefly found on the downs of Kent and Sussex.
Used to be common on Deal sand-hills—now
devastated by golf! The tint in this is brown,
in the former red.

H. (Hygromia) rufescens.—A flattish, dark
brown shell, abundant in the south of England,
and not rare elsewhere. Has a semi-lunar mouth
with a white internal rib. In gardens seems to
prefer violet beds.

H. (Hygromia) hispida, t.e. hairy.—These hairs
are deciduous, and the hairless variety used to be
considered a separate species under the name of
concinna (t.e. neat), but would now be the variety
depilata, or bald. Broad and deep umbilicus.
Common, except in Ireland. Usually associates
with H. vufescens in moist places.

H. (Hygromia) granulata is also hairy with white
silky bristles. Yellowish in colour. Shell thin.

AA Our British Snails

Local, but abundant where found. Its umbilicus
is very small. It falls from its food plants at the
least shake.

H. (Hygromia) revelata.— Scantily haired.
Globular thin shell. Pale green. Mainly found
in Cornwall and South Devon. In cold or dry
weather it buries itself rather deeply.

H. (Hygromia) fusca.—Very thin, glossy, brown
shell. Local. Hardy, and even active in frost.
Chiefly found on nettles, which many shells
like as food, though avoiding the commonly
associated horehound.

H. (Euparypha) pisana.—First noticed at Pisa.
Somewhat like Helicella virgata, but larger,
sub-globular, and solid shell, yellowish-white
with dark lines or bands. Aperture or mouth
yellowish or rosy. Most common in Portugal
and Morocco, and all round the Mediterranean,
dry places, especially near the sea. In England
chiefly confined to Tenby and other parts of
Pembrokeshire; also in the Channel Islands.
Varies much in tint and markings. Swarms
where found; it loves sun and heat. Seems
to lend itself better to colonization than mest
species.

H. (Helicella) ttala—So named by Linneus,
who probably received it first from Italy. Shell
almost circular, flat. Umbilicus very large and
open. Common on heaths and downs, especially
near the sea.

Our British Snails 45

H. (Candidula) caperata.—(The specific name
means wrinkled, like a goat’s horn.) Careless of
heat or cold. Distinguished from the young of
FH, virgata by being more depressed, having a
larger umbilicus, regular and strong striation,

Helicella virgata at rest on thistle, natural size.

and round mouth with white internal rib. Found
under stones and on grass. Common.

fH. (Heliomanes) virgata (i.e. striped).—A very
variable shell. See the illustration above of

46 Our British Snails

some at rest on thistles. “Local sbut vem
abundant where found. Whitish shell with dark
bands, but a yellowish and a white variety
usually is found with the type. The most
beautiful variety, vadiata, is chiefly found in
Romney Marsh, and from Hythe to Rye.

H. (Turricola) terrestyris—A Mediterranean
species, well established since 1890, in one spot
near Dover. A pyramidal shell, greyish, with
one dark band on each whorl.

H. (Cochlicella) barbara (i.e. foreign).—Long,
conical, whitish, with one dark band. By the
sea-coast. In shape somewhat hke a Buliminus.

We come now to the Pupa family and its genus
Buliminus and its sub-genus Ena. It is repre-
sented by :—

Ena montana.—A local and southern shell,
conical, slightly glossy, brown. Lip white and
deflected. Commonly found on the holes of
smooth-barked trees, and it closely resembles
the small knobs on beech trunks.

Ena obscura.—Like the former, but much
smaller, and found nearly everywhere in England
and Wales. Found in hedgebanks, or on beech
trunks. Its specific name is derived from its
habit of covering itself with a coating of earth,
and so becoming inconspicuous.

The plate on p. 47, gives figures of some of our
smaller shells, enlarged in most cases so that their
distinguishing marks can be seen. The upright

‘Some of our smaller shells. Actual size indicated by the
upright line.

48 Our British Snails

line by the side of each figure gives its actual
height. The shells as numbered are Helix
rupestris, H. pygmea, H. pulchella, H. lapicida,
H. obvoluta, H. terrestris, H. barbara, Ena montana,
Ena obscura, Pupa secale, P. anglica, P. cylin-
dracea, P. muscorum, Vertigo antivertigo, V.
moulinsiana, V. pygmea, V. alpestris, V. sub-
striata, V. pusilla, V. angustior, V. edentula, and
V. minutissima. Without a magnifying glass
it will be seen that it would be very hard to
distinguish some of the minute shells, but this
enlargement enables us to see the characteristic
denticles in the mouth, and the presence or ab-
sence of striations on the shell.

Pupa (Abida) secale is named frcm the Latin
for rye, a grain of which the shell mcre or less
resembles. Conical, brown, mouth horseshoe-
shaped with eight white denticles. Our largest
Pupa. Local, but abundant where found. Pre-
fers calcareous rocks or woods.

Pupa (Lauria) anglica—Small, ovate, purplish
in colour ; mouth like that of secale. Lives in moss,
mainly in the north of Britain.

Pupa (Lauria) cylindraceanx—Small, cylindri-
cal, paler than the last ; thick and reflected white
lip with one denticle. Abundant. On stones,
in moss, under leaves and bark.

Pupa (Jaminia) muscorum.—Common, especi-
ally on sandy soils near the sea. Mouth nearly
circular, whereas in the two former species it

Our British Snails AQ

is horseshoe-shaped. The lip is thin and not
reflected.

The genus Vertigo (7.e. twisted, the Latin equiva-
lent of the Greek Helix) containsshells even smaller
than the Pupe, about the size of a pin’s head.

Vertigo (Alea) antivertigo (t.e. not reversed
or sinistral, as are V. pusilla and V. angustior).
Semi-transparent, glossy, horn-colour, with den-
ticles (as have all except V. edentula and V.
nmunutissima). Found in nearly all counties in
moist places.

Vertigo (Alea) moulinsiana.—Our _ largest
species, though only 23 millimetres in height.
Mainly in marshy places. Not common.

Vertigo (Alea) alpestyis—Rare and_ local,
chiefly northern. Nearly transparent shell.

Vertigo (Alea) pygm@a.—Common, and often
in colonies at roots of grass and under stones and
logs. Not confined to moist places.

Vertigo (Alea) substriata—Local. Strongly
striated.

Vertigo (Vertilla) pusilla.—Sinistral, as is also

Vertigo (Vertilla) angustior—Both species rare
and local. The former is the larger and broader.
In the former the last whorl is broadest, in the
latter the penultimate. In the former the mouth
is semi-oval, in the latter triangular. In the
former the outer lip is very slightly, in the latter
very deeply contracted. The former has 6 to 7
teeth, the latter 4 to 5.

D

50 Our British Snails

Vertigo (Sphyradium) edentula is dextral and
without denticles. Perhaps the most common
Vertigo. Partial to bracken.

Vertigo (Isthnua) minutisstma.—Dextral and
without denticles. Smaller, narrower, and more
strongly striated than edentula, but rarer. All
the Pupe should be examined with a magnifier.

Balea perversa (t.e. sinistral) is a much larger
shell belonging to the Clausilia family. Thin,
dark horn-colour, semi-transparent, glossy, 7 to §
whorls, local, but abundant where found. Chiefly
found on trees.

Clausilia (Pirostoma) bidentata.—All our British
clausilias are sinistral. The clausilium (little
door) is an internal contrivance fastened to the
pillar of the shell (whereas an operculum is
attached to the body of a mollusc) by an elastic
ligament to protect it against insect enemies
when the animal withdraws. Bidentata has two
denticles, fusiform and reddish-brown, as are
all. Very common on walls and trees.

Clausilia (Pirostoma) rolphit.—Rare and local.
Almost subterranean in habit. More coarsely
striated than the last. The upper whorls nearly
of the same breadth, forming a short cylinder.

Clausilia (Alinda) btplicata—Very _ local.
Chiefly on Thames willows. Larger than the
two former, and streaked with white.

Clausilia (Marpessa) laminata.—Much like the
former, but widely distributed. Usually found

Our British Snails 51

on beech and ash trees, and on limestone rocks.
Smooth and glossy.

In the family Stenogyra we have three genera,
Azeca, Cochlicopa, and Cecilioides (with also
the imported Stenogyra Goodallit, found only
in pine-houses).

Stenogyra (Azeca) tridens is a small chrysalis-
shaped, solid but semi-transparent shell, horn-
coloured, with 3 denticles. Not rare in moist
places.

Stenogyra (Cochlicopa) lubrica (i.e. slippery).—
Very common in moss and under stones or logs.
Much like the previous species, but no denticles
and fewer whorls, and broader mouth.

Stenogyra (Cecilioides) acicula—Ilf this word
is supposed to be Latin it would mean either
“like to a blind worm ”’ or “like to a lettuce ”’ !
Cacus, however, being Latin for blind, the allusion
is no doubt to the fact that this wholly subter-
ranean species is eyeless. The only British
representative of a large family of carnivorous
molluscs. I have found it on Saxon bones when
unearthed, and in crevices of limestone under-
ground, but it is generally found dead amongst
the rejectamenta on the banks of rivers. It
is a pretty, glossy white shell, 5 millimetres in
height by 1 in breadth.

I may notice here two other land shells, al-
though they scientifically are grouped amongst
the fluviatile Gasteropoda.

52 Our British Snails

Cyclostoma (Pomatias) elegans —Common on
calcareous soils, especially chalk. A spiral shell
of 4$ whorls, suture very deep. Mouth circular
(whence its name) and provided with a thick
shelly operculum which closes the orifice when
the animal retires by means of an elastic ligament.
This and the next species are our only land shells
provided with an operculum, and this shows their
derivation from the marine Gasteropoda (e.g. whelk
and winkle). Perhaps all shells were originally
marine, but some became first amphibious and
then terrestrial. It is quite unlike any other of
our land shells.

Acicula lineata is a very small shell, the size
of the Pupz; mainly northern in distribution.
Feeds on liverworts and fungi. Very local ;
6 or 7 whorls. Mouth pear-shaped, with a horny
operculum.

The Family Succinea really ranks with the land
shells, as belonging to the sub-order Pulmonata
or lung-breathing molluscs. It is, however,
amphibious, and hibernates in the mud at the
bottom of a ditch.

Succinea putris (it is the mud, not the animal,
which is putrid !) is called the Amber Snail from
the colour of its shell, which is unlike any other.
Common on flags, etc., at the edges of ditches
and ponds.

Succinea elegans.—Difficult to distinguish from
the former, but the animal is darker and the shell

Our British Snails 53

more slender, with a deeper suture and a narrower
mouth.

Succinea oblonga is local and rare. Generally
found near the sea. Much smaller than the
other Succineas, and easily mistaken for the
young of other species. Colour dull greenish.

The family Auriculide is represented in Britain
only by Carychium minimum; a very small,
semi-transparent, white and glossy shell found
under mossy stones and other moist places.
Common, but sharp eyes are needed to find it.

We now come to the freshwater shells, which
we capture best by means of a perforated scoop,
whether they are on the waterweeds or hidden
in the sand or mud of the bottom.

It may be noted that all freshwater shells are
greenish-brown which is an excellent protective
colouring as rendering them less visible among
water weeds to the fish, which devour them
ereedily.

The family of Limneeide (or lake dwellers) has
the sub-families, Planorbis, Physa, Limnza, and
Ancylus. In the Planorbine (7.e. flat-coiled) the
only representative of the genus Segmentina is
Segmentina mitida, a small, quoit-shaped, keeled,
semi-transparent, light brown shell, with internal
divisions like those of a nautilus which are visible
tronyethe outside of the Shell. Local. Found
in stagnant or sluggish water. The genus

54 Our British Snails

Planorbis contains the sub-genera Hippeutis,
Gyraulus, Gyrorbis, Coretus, and Bathyomphalus.

Planorbis (Hippeutis) fontanus is much like
Segmentina but has no septa, afid is flatter.
Common, especially on watercress. Often encrusted
with mud.

Planorbis (Gyraulus) nautileus is very small ;
quoit-shaped, with the upper side flat. Grey and
striated. The variety crista has the ridges of
the epidermis drawn into points, and is beautiful
when seen by a magnifying glass. Common in
ponds and ditches.

Planorbis (Gyraulus) dilatatus is a very small
shell imported in cotton bales from America,
and naturalized in canals in Lancashire. No
other of its kind is so small.

Planorbis (Gyraulus) albus is dull white and stri-
ated. Flattish above, with spire depressed. Fre-
quently encrusted and black with mud. Common.

Planorbis (Gyraulus) parvus (but not so small
as dilatatus)—Convex above with a central de-
pression, concave beneath. Suture deep, and
umbilicus large. Smooth and glossy. Local.

— Planorbis (Gyrorbis) spirorbis.—Very flat, glossy,
brown, whorls 5 to 6. Common in ponds and
ditches.

Planorbis (Gyrorbis) vertex.—Very like the last,
but flatter and thinner, and with a prominent
keel. More local than spzvorbis, but sometimes
found with it. Whorls 6 to 8.

Our British Snails 55

Planorbis (Gyrorbis) carinatus.—Larger than
spirorbis and vertex. Sharply keeled in the
centre of the. outer margin. Mouth angulated
above and below. Local, mainly in the south
and east of England.

Planorbis (Gyrorbis) umbilicatus.—Like the last,
but the keel is below and not on the centre.
Mouth rhomboidal. More common than cart-
natus.

Planorbis (Coretus) corneus.—Far the largest
species. Dark brown, lighter below. Mouth
nearly circular. Spire sunk. In boiling water
often exudes a crimson fluid. Common.

Planorbis (Bathyomphalus) contortus.—Small, 8-
whorled, flat above, very convex below. Fairly
common in still water. Very compact in appear-
ance.

The sub-family Physa has two genera, Aplecta
and Physa.

Physa (Aplecta) hypnorwm is a spindle-shaped,
very glossy, semi-transparent, dark reddish brown,
shell, with 6 to 7 whorls. Not common. Found
in still water.

Physa (Physa) fontinalis—More common, and
found in running as well as in still water. Shorter
and more rounded than the last. Shell very
thin, greenish horn-colour. Lobes of the mantle
expand over the shell. Seen in an aquarium
are its perpendicular threads of mucus, up and
down which the animals climb.

56 Our British Snails

Limnea (Amphipeplea) glutinosa.—Very local.
Somewhat like Ph. fontinalis, bat larger and more
thin. In young specimens the mantle covers
the shell, and in adults the animal is not wholly
contained in the shell.

Limnea (sub-genus Radix) «involuta.—-Only
found in one Irish tarn. Whorls envelop the
spire. Very thin, pale amber.

Limnea (Radix) peregraa—The most common
and variable of all our freshwater shells. Spire
pointed. Somewhat amphibious. Found practi-
cally over the whole of the Eastern Hemisphere.

Limnea (Radix) auricularia.—Mouth very large,
with outer lp widely reflected. Very common
and fime in «the Thames, Spire very {shor
apex sharp.

Limnea (sub-genus Limnophysa) stagnalis.—
The largest of the genus. Common, except in
Wales. Shell greyish, spire long and tapering
to a point; 12210 teeth on its lingual ribbon.
See the illustration on p. 57, which also shows
above two specimens of Paludina contecta, one
being covered (as freshwater shells often are) by
a vegetable growth, which obscures the marking.

Limnea (Limnophysa) palustris.—Shell tapering,
somewhat solid, brown, much smaller than stag-
nalis. Common in slow or stagnant water.
Some varieties much darker than the type.

Limnea (Limnophysa) truncatula—Like the
last in shape, but much smaller, and with a deeper

Our British Snails yi

suture. Common, and fond of being out of the

Paludina contecta (two)
and Limnea stagnalis
on water-weeds.

58 Our British Snails

water. A parasite of this mollusc causes “ fluke ”’
in sheep which have taken it in by drinking or
by eating grass by the side of ponds and ditches.

Limnea (Omphuiscola) glabra.—Also amphibious.
About the same size as truncatula. Local.
Inner lip rather thick and reflected on the base
of the penultimate whorl.

Limnea (Ancylus) fluviatilis —‘ Freshwater
limpet.’’ Shell, rather impet-like, with a hooked
apex (whence its generic name), adheres to stones
or piles in running water. Common. I once
dredged a large water-beetle with three of these
shells adhering to its wing-cases; thus it would
be transported to fresh habitats.

Limnea (Acroloxus) lacustvis.—Like the former
but more local, and preferring sluggish or still
waters. Shell more oblong, thinner, and apex
twisted to the left instead of to the right as in
fluviatilis.

The sub-order Pectinibranchiata (comb-like
gill) contains the genera Neritina, Paludina, and
Valvata, in all of which there are two tentacles
with eye at the base, and an operculum to the
shell.

Nernitina fluviatilis.—Solid, glossy, chequered
brown, white, and purple (but also a lemon-
coloured variety). Operculum semi-lunar, orange,
with a projection which serves as a lock to keep
the operculum in position. Not rare in England ;
on stones in running water. See illustration

Our British Snails | 59

below, which also shows above L. (Ancylus)
fluviatilis. i

Paludina (Vivipara) contecta.—Shell dark green
with darker bands. Conical. Suture very deep.
Operculum horny. Viviparous. Local.

Paludina (Vivipara) vivipara.—More common
than contecta. Shell more oval, not so glossy,
light greenish yellow, suture not so deep, no
umbilicus, apex blunt.

Neritina and Ancylus.

Paludina (Bythinia) tentaculata.—(The eyes in
this genus are not on foot-stalks ; the operculum
is shelly instead of horny). Common in slow
water and ditches. Shell semi-transparent, yel-
lowish, mouth oval, angulated above. Operculum
made of plates rising one above another formed
at different stages of growth.

Paludina (Bythinia) leachit.—Much smaller and
less common than the last. Distinct umbilicus ;
mouth almost circular.

Paludina (Paludestrina) ventrosa.—A_ brackish-

60 Our British Snails

water shell, swarming where found, e.g. from
Erith to Gravesend, and in East Anglia. Shell
small, thin, semi-transparent.

Paludina (Paludestrina) jenkinsi.—A larger shell,
not confined to brackish water and spreading
very rapidly. Swarms where found. A variety
has a marked keel which sometimes bears bunches
of spines at equal distances.

Paludina (Paludestrina) stagnalis—Larger and
with more whorls. Not so common.

Paludina (Pseudamnicola) anatina.—Small, sub-
conical, deep suture. Found in brackish water,
and apparently identical with Hydrobia cr
Paludestrina similis, which I used to find by
the Thames, where it is now apparently extinct.

Valvata piscinalis.—Globular, suture very deep,
circular mouth, operculum concentrically spiral.
In ponds and slow water. Shell yellowish, but
commonly covered with conferva.

Valvata cristata.—Much smaller; shell disk-
shaped. Frequents the roots of flags. Shell
striated and more or less ridged, but the name
cristata refers to the plume-like appearance of
its breathing apparatus.

We now come to the bivalve shells with leaf-
like gills. The Unionide contain two genera,
Unio and Anodonta, commonly called fresh-
water mussels.

Unio tumidus.—Shell ovate, very solid, dark

Our British Snails 61

brown ; common. See accompanying illustration,
which shows the fringed branchial siphon which
draws in food-bearing water, and the smaller
anal siphon by which it gets rid of undigested
matter.

Unio pictorum.—More oblong and thinner shell,

Freshwater mussel breathing and eating.

yellowish, girdled with brown in the lines of
growth. Common. The specific name recalls
that gold and silver paint used to be sold in
these shells (or marine mussels) for iluminating
work. It is said to produce 220,000 eggs in the
three summer months.

Unio (margaritana) margaritifer.

Shell solid

62 Our British Snails

and black, beaks always eroded. Mainly found
in mountain streams. Its pearls are few and
poor compared with those of marine shells ; but
they attracted the notice of Cesar and so hastened
the conquest (and development) of Britain.

Anodonta cygnea.—(In this genus the hinge
is toothless, whence its generic name. The specific
names cygnea and anatina mean ‘‘swan’”’ and
“duck,” in reference to their comparative size).
This is the largest of our freshwater shells, reach-
ing even g inches in breadth by 4% in length.
Common in ponds and slow water. Sometimes
the shells are yellowish green with rays of the
same colour.

Anodonta anatina.—Doubttful if this is a sepa-
rate species or only a smaller form. The hinge
line is raised instead of being straight, and the
posterior side slopes abruptly instead of gradually.

In the next family are two genera, Spherium
and Pisidium.

Spherium corneum.—Very common. Shell some-
what globular, glossy, opaque, horn-coloured,
marked with lighter bands in the line of growth.
Usually on the bottom, but can suspend itself
by threads of mucus.

Spherium rivicola—Much larger. Also flatter
and more striated. Yellowish brown or greenish.
A whole series of young of different sizes will be
found in the animal.

Spherium pallidum.—tLocal in canals and

Our British Snails 63

ponds. Oblong. Distinguished also from the
previous species by the body being milk-white,
and the shell is ashy-grey.

Sphenium lacustre—Local. On the beaks is
a calcareous nucleus which distinguishes it. It is
thinner than corneum, and rounder than pallidum.

Pisidium amnicum.—(Our five pisidia resemble
Spherium, but are much smaller, all but amnicus
being minute. Very abundant where found.
P. amnicum and fortinale are triangular in shape,
P. pusillum oval, P. nitidum round, and P. roseum
or milium oblong; but they are difficult to
distinguish on account of their similarity and
variation). P. amnicum is nearly twice the size
of the others, and this and fontinale may be
found in slow rivers, whereas the others prefer
stagnant waters.

Pisidium fontinale-—Smaller and thinner, and
with more prominent beaks than P. amnicum.

Pisidium pusillum.—The most common species.
Distinguished from the last by being oval and
by its beaks being blunter and more central.

Pisidium nitidum.—Rare. Very glossy and
striated.

Pisidium roseum (from the colour of part of its
body).—Like mitzdum, but oblong, with a straight
lower margin, and with beaks placed away from
the: centre:

The last shell to be mentioned could not be
mistaken for any other. It belongs to the

64 Our British Snails

sub-order Heteromya (t.e. with adductor or
closing muscles not equal); to the family of
Mytilide (or mussels) and the genus Dreissensia
(named after a Dutch conchologist).

Dreissensia poiymorpha is a triangular, boat-
shaped, bivalve, supposed to have been intro-
duced with Russian timber (as was also probably
Hydrobia Jenkinst). It is gregarious, and at-
taches itself to objects by a byssus like our marine
mussels. Shell yellowish-brown with wavy pur-
plish lines, wrinkled in the line of growth. Com-
mon in the New River, and has been found in
iron water-pipes in Oxford Street.

All our shells have varieties (many an
albino or white form), and the collection and
distinguishing of these varieties, which in some
species are numerous, adds much to the interest
of the collector. In addition there are also the
variations in size or markings which can hardly
rank as varieties. Inasmuch as none of our
shells are peculiar to our country (which
is from the natural history and the geological
point of view only a detached portion of the Conti-
nent), it may be well to warn young collectors
that if they receive shells from the Continent,
mere varieties are there often named as separate
species and variations considered as definite
varieties. This is especially the case with Heli-
cella virgata.

Our British Snails 65

As to the arrangement of shells in a collection
before a regular cabinet is obtained, the tinier
shells may be kept in small glass tubes with corks
(such as used for homoeopathic medicines), and
the medium sized ones in the trays of common
matchboxes, these being arranged in large shallow
glass-covered trays which can be obtained from
any cardboard boxmaker at a small cost, and
several of these, stored one above the other,
form an excellent substitute for a more costly
cabinet. In all cases the name, and the place
where the shells were found, should be written
on a small slip of card placed in the tube or tray.
It is not well in most cases to fasten the shells
on card, but if this is done gum tragacanth is best.
The collection should be kept free from damp and
from dust.

HINTS FOR COLLECTING AND PRESERVING
SHELLS OF MOLLUSCS.

The following notes supply a few general rules
as to finding and preserving shells :—

Of Shell-bearing Molluscs there are three
classes—Marine, Freshwater, and Land. The
first two include Univalves and Bivalves, the
last only Univalves.

I. MARINE SHELLS may be obtained, Ist, by
searching on and under rocks at low water, or
on coral reefs, among seaweed attached to them,

E

66 Our British Snails

or floating on the sea, or on a sandy beach.
Bivalves may be found by digging in the sand,
or mud, on a beach, or at the mouth of a river:
their presence is generally indicated by a circular
breathing hole in the sand. 2nd. By dredging,
by which means only deep-sea shells can be ob-
tained ; but after a storm these may often be
found upon the shore, before they have lost their
lustre.

Limpets, etc., should be detached with a thin
blade passed quickly under the shell, taking care
not to break the edges. Small shells on and in
seaweed, and limpets, etc., adhering to stones
will drop off and sink to the bottom in a vessel
of cold fresh water.

2. FRESH-WATER SHELLS may be obtained in
any river, lake, pond, marsh or reservoir. Uni-
valves, chiefly on the banks, on reeds and plants
growing near the hedges, and on the under surface,
leaves, and stems of aquatic plants. Bivalves
generally at the bottom, among stones, or buried in
the sand, or among the roots of aquatic plants.

3. LAND SHELLS.—These resemble, more or
less, in their habits the garden snail, though
varying greatly in character, size, and colour.
They mostly abound in a chalk or limestone
district, and in moist and wooded situations.
Some species inhabit low and damp spots, roots
of trees, hollows and crevices of rocks and walls ;

Our British Snails 67

some lie under stones or pieces of wood, or in the
earth; others climb shrubs, and in tropical
climates even lofty trees. Their haunts vary
according to the weather and the season. They
come out early in the morning, and after rain.
Some bury themselves in moist places during the
dry season, or burrow under leaves, grass, or
stones, often closing the mouths of their shells
with a white secretion to prevent evaporation
during the period of hibernation.

The smallest shells, especially of land species,
and young imperfect shells should be collected.

In all cases “‘ live shells,’ z.e. shells in which
the animal is alive, are to be chosen; but, when
these cannot be procured, “‘ dead shells,’’ which
have not lost their lustre, or their colour, especially
those of rare species, should be preserved.

With regard to the mode of Preserving Shells.

1. No attempt should be made to clean them,
or to remove the furry skin, more or less thick,
with which they are often covered, beyond re-
moving with a soft brush any mud or sand
adhering to them.

2. The animals of Land and Freshwater shells
may be killed by immersing them for a few
minutes in boiling water, after which the bodies
may be easily extracted whole with any suitable
instrument, ¢.g., a fork or a pin, according to
size. Hot water should not be used with marine
shells : it often destroys theirlustre. They should

68 Our British Snails

be buried, if time permits, in sand, or other dry
material, until the animal dries up (in small shells)
or rots (in large specimens); or they may be
drowned in cold fresh water, and hung up in
the air to dry or rot away. In the former case,
if an operculum (with which some species, both
marine and land, close their mouths, more or
less partially) exists, it will, generally in the case
of land shells, remain in its place, adhering to
the shell: In the latter, the decayed matter
should be washed out, and the operculum, if any,
replaced and fixed, say, on cotton filling the shell.
This applies equally to land shells.

3. Care should be taken not to injure the
edge or lip of the mouth of univalves, or the
ligament of the hinge of bivalves. When bivalves
gape on dying in water, or if the ligament be
broken, the valves should be closed and tied
together. If the hgament of a gaping bivalve
should become dry and stiff, it can be softened
by putting it in water.

4. The localities in which each species is found
should be noted, and, in the case of dredging, the
depth of water.

With regard to the mode of packing Shells for
LTvansport.

All solid shells may be wrapped in one or two
folds of paper of any kind. Fragile and minute

Our British Snails 69

shells should be put, generally separately, into
a box or bottle—with or without cotton, as
required. Such packets may be heaped up in
any box, heavy shells at the bottom, without
pressure, and any blank filled at the top with
paper or other elastic material. Sawdust injures
the lustre of many species.

Two books on shells should be procured at
an early stage of the collector’s career, which
will give not only minute descriptions of all
our land and freshwater shells and their varieties,
but also plates of illustrations. These are the
Collector's Manual, by L. E. Adams, 2nd ed.,
published by Taylor Brothers of Leeds; and
Rimmers’ Land and Fresh Water Shells, published
by George Grant of Edinburgh.

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