On [plate E], and fig. 1 and 1 a, may be seen an insect which somewhat resembles the oak egger-moth, and is often mistaken for it by inexperienced eyes. This is the “Drinker” moth, remarkable for the thick furry coat which it wears, as a caterpillar and as a moth, and which it employs in the construction of its cocoon. This moth is one of my particular friends; and I have had hundreds of them from the egg to their perfect state. I had quite a large establishment for the education and development of lepidoptera, and especially favoured the tiger-moth, the oak egger, and the drinker.
The caterpillar of this moth is entirely covered with dense hair, even down to the very feet; and by means of this protection it is enabled to brave the winter frost, needing not to pass the cold months in a torpid state. It is a pretty caterpillar, and very easily recognised by the figure. Its chief peculiarities are the two tufts of hair that it bears at its opposite extremities, and the double line of black spots along its sides.
Generally, it feeds on various grasses, but it is not dainty, as are many caterpillars; and I have always found it to eat freely of the same food as the oak egger larva. This caterpillar is seen at fig. 1 b.
When alarmed, it loosens its hold of the plant on which it is feeding, rolls itself into a ring, and drops to the ground, hoping to evade notice among the foliage. This habit used to be rather perplexing to me, not because the creature could escape by so well-known a trick, but because it would not go into the box prepared for its reception.
It is necessary to have a box of a peculiar form for the collection of caterpillars. If the lid is raised every time that a fresh capture is made, difficulties increase in proportion to the number of caterpillars. For, when some thirty larvæ are in the box, they all begin to crawl out when the lid is opened; and Hercules had hardly a more bewildering task among the hydra’s heads than the entomologist among his captives.
No sooner is the light admitted, than a dozen heads are over the side; and as fast as one is replaced, six or seven more make their appearance. The only remedy is to sweep them all back with a rapid movement of the hand, to shake them all to the bottom, and then to replace the lid as fast as possible. Even with all precaution, caterpillars are crushed; and, besides, they are delicate in their constitutions, and require gentle handling.
So the best plan is to have a tin box made with a short tube, through which the caterpillars can be introduced, and which can be stopped by a cork when the creatures are fairly inside.
Now, although this is a capital contrivance for caterpillars that hold themselves straight, it fails entirely when they curl themselves into a ring and refuse to be straightened. It is as impossible to straighten a rolled-up hedgehog as a caterpillar in a similar attitude; and if force is used in either case, the creature will be mortally injured. However, gentle means succeed when violence fails, with insects as with men. A Bheel robber will steal the bedding from under a sleeping man without waking him; and, by an analogous process, the refractory caterpillar is lodged in his prison before he is fairly awake to his condition.
The entomologist feels a justifiable pride in executing similar achievements; for there is quite as much force of intellect needed to outwit a caterpillar as a quadruped.
When the drinker caterpillar passes into its pupal state, it makes for itself a very curious cocoon, not unlike a weaver’s shuttle in shape, being large in the middle, and tapering to a point at each end. The texture is soft and flexible, as if the cocoon were made of very thin felt, and the larval hairs are quite distinguishable on its surface. The moth leaves the cocoon about August. For the cocoon see fig. 1 c.