When staying at Box Hill, near Dorking, I oftenp. 147 saw the great apple snail, Helix Pomatia, which is only found on chalk soils, and is supposed to have been introduced by the Romans, from the quantities of their empty shells found with Roman remains in all parts of England. They were kept and fattened in places called "Cochlearia" and made into various "dainty dishes" which the Romans thought quite fit to set before their kings. It is certain that they are very nutritious creatures, and that in times of famine people have supported life and kept themselves mysteriously "fat and well-liking" by resorting to snails and slugs as articles of diet. Indeed I have heard more than once that the famous "PÂte de Guimauve" owes its healing nutritive character to this despised univalve, which is said to enter largely into its composition. I brought several apple snails home with me from Box Hill and kept them for many years, until I really believe the creatures, in a dim sort of way, recognized me as their friend, or at any rate their feeder. I cannot boast, as I believe an American lady is said to have done, that "her tame oysters followed her up and down stairs," but certainly my snails would, when placed uponp. 148 the lawn, very frequently crawl towards me, and would do so again and again when removed to a distance. As the weather became cold they always hibernated, closing the mouth of the shell with a thin, firm covering, or operculum, of chalk, which, mixed with their slime, made a substance like plaster of Paris. Thus enclosed they would lie as if dead until the warmth of the following spring made them push the door open and come out, with excellent appetites, ready to eat voraciously to make up for their long fast. These Roman snails were quite five inches long when fully extended, and therefore were much larger than our English species; the body was cream colour and the shell a pale tint of buff varying somewhat in different specimens.

These creatures were kept in a fern case with glass top and sides, and it was singular to observe the way in which they could suspend themselves (as shown in the drawing) from the top of the box.

The substance which exists in the caterpillar of the silkworm moth, and which can be drawn out into fine shreds of silk, is very similar to thep. 149 slime of the snail, only in the latter it is not filiform, but exudes as a liquid and then hardens into a thin layer of silk which is strong enough to support the weight of two of these snails, for, seeing them one day thus suspended, I put them in the scales and ascertained that the weight of the two amounted to 2 ½ ounces.

This mucus forms the glistening, shiny track which the snail leaves behind it, enabling it to glide easily and painlessly over rough substances which would otherwise lacerate its soft body.

One hardly expected to find social feeling and affection in animals so low down in the scale of nature, but I do not know what else could have led my "Romans" to caress each other with their long horns by the hour together and always keep close to one another, twisting and curling their yielding bodies round each other in the most odd contortions. Our English snails hibernate in whole colonies for the winter, which also points to their affectionate and gregarious habits.

In lifting up some moss I once came upon some yellow, half-transparent eggs about as large asp. 150 pearl barley, and wishing to know what they would prove to be I kept them in damp moss under a tumbler for about a fortnight, when, to my dismay, I found a grand colony of yellow slugs! and not a little was I teased about these interesting young people. I am afraid I must own they were given as a bonne bouche to my Virginian nightingale, who seemed highly to approve of this addition to his daily fare. Snails' eggs are nearly white and semi-transparent; the empty shells of young snails are very lovely when placed in a good microscope: the polariscope bringing out their exquisite prismatic tints.

The gardener one day brought in a testacella, or shelled slug. It fed upon earth-worms and was quite unlike the ordinary black or grey slug, of which we have, alas! countless thousands preying upon all the green things of the earth. This shelled slug was yellow, and seemed able to elongate its body very differently to any other species. The shell was quite small, a simple dome-shaped plate upon the anterior part of the body. I kept it for some weeks on damp moss under a tumbler, but it was often able to escapep. 151 by flattening itself to a mere thread and then crawling under the rim of the tumbler, and at last I gave it liberty as a reward for its persevering efforts to obtain its freedom.

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