CHAPTER VII
THE ARBUTUS CATERPILLAR
I have not found many species of urticating caterpillars in the small corner of my investigations. I know of two only: the Pine Caterpillar and the Arbutus Caterpillar. The latter belongs to the genus Liparis. His Moth, who is a glorious snowy white, with the last rings of the abdomen bright russet, is very like Liparis auriflua, Fab., from whom she differs not only in size—she is smaller—but, above all, in the field of operations selected by her caterpillar. Is the species classified in our lists? I do not know; and really it is hardly worth while to enquire. What does a Latin name matter, when one cannot mistake the insect? I shall be sparing of detail concerning the Arbutus Caterpillar, for he is far less interesting in his habits than the Pine Processionary. Only his ravages and his poison deserve serious attention.
On the Sérignan hills, sunny heights upon which the Mediterranean vegetation comes to an end, the arbutus, or strawberry-tree, [[151]]abounds: a magnificent shrub, with lustrous evergreen foliage, vermilion fruit, round and fleshy as strawberries, and hanging clusters of little white bells resembling those of the lily of the valley. When the frosts come at the approach of December, nothing could be more charming than the arbutus, decking its gay verdure with both fruits and flowers, with coral balls and plump little bells. Alone of our flora, it combines the flowering of to-day with the ripening of yesterday.
Then the bright-red raspberries—the darbouses, as we call them here—beloved by the Blackbird, grow soft and sweet to the palate. The housewives pluck them and make them into preserves that are not without merit. As for the shrub itself, when the season for cutting has come, it is not, despite its beauty, respected by the woodman. It serves, like any trivial brushwood, in the making of faggots for heating ovens. Frequently, too, the showy arbutus is ravaged by a caterpillar yet more to be dreaded than the woodcutter. After this glutton has been at it, it could not look more desolate had it been scorched and blackened by fire.
The Moth, a pretty little, snow-white Bombyx, [[152]]with superb antennary plumes and a cotton-wool tippet on her thorax, lays her eggs on a leaf of the arbutus and, in so doing, starts the evil.
You see a little cushion with pointed ends, rather less than an inch in length; a white eiderdown, tinged with russet, thick, very soft and formed of hairs fixed with a little gum by the end that points towards the upper extremity of the leaf. The eggs are sunk in the thickness of this soft shelter. They possess a metallic sheen and look like so many nickel granules.
Hatching takes place in September. The first meals are made at the expense of the native leaf; the later ones at the expense of the leaves all around. One surface only is nibbled, usually the upper; the other remains intact, trellised by the network of veins, which are too horny for the new-born grubs.
The consumption of leaves is effected with scrupulous economy. Instead of grazing at hazard and using up the pasturage at the dictates of individual caprice, the flock progresses gradually from the base to the tip of the leaf, with all heads ranged in a frontal attack, almost in a straight line. Not a bite is taken [[153]]beyond this line, until all that lies on this side of it is eaten up.
As it advances, the flock throws a few threads across the denuded portion, where nothing remains but the veins and the epidermis of the opposite surface. Thus is woven a gossamer veil serving as a shelter from the fierce rays of the sun and as the parachute which is essential to these weaklings, whom a puff of wind would carry away.