[Illustration: Fig. 192.--The Convolvulus Sphinx (_Sphinx convolvuli_).]
This is the mission of science, to dissipate the thousands of prejudices and dangerous superstitions which mislead ignorant people.
[Illustration: Fig. 193.--Death's-head Hawk-Moth (_Acherontia atropos_).]
This moth has the front wings of a blackish brown colour, having lighter irregular bands varied with brown and grey, above and below. On the middle of the front wing there is a well-defined white dot. The hind wings have two black bands, the upper narrower than the lower one; the rest of the wing is a fine yellow. The abdomen has likewise from five to six yellow and as many black bands; in the middle is a long blackish longitudinal band. This moth is not very rare, and may be found in autumn. Its flight is heavy, and, as we have said, the insect never flies till after sunset. If caught, or when teased, it utters a cry which is very audible.
The death's-head hawk-moth would be a very inoffensive being if it did not make its way into bee-hives, in order to steal the honey, of which it is excessively fond. It is to no purpose that the bees dart their stings at the intruder, they only blunt them against its thick skin, and soon, terrified at its presence, disperse on all sides.
[Illustration: Fig. 194.--Larva of the Death's-head Hawk-Moth (_Acherontia atropos_).]
The caterpillar of the _Acherontia atropos_ (Fig. 194) is the largest of all European caterpillars. It attains to as much as four and a half inches in length by eight lines in diameter. Its colour is lemon yellow, which changes into green on the sides and belly. From the fourth to the tenth ring inclusively it is ornamented laterally with seven oblique bands of an azure blue, which are tinted with violet, and bordered with white on the side. These bands joining together over the back of each segment resemble so many _chevrons_ placed parallel to each other. The body is, moreover, dotted with black. At its extremity is a yellow horn, curved back like a hook, and covered with tubercles. The head is green, and marked laterally with a black stripe. It lives chiefly on the potato, and the _Lycium barbarum_, sometimes called the tea-tree, a shrub belonging to the _Solanaceæ_. It buries itself in the earth to change into a chrysalis (Fig. 195) of a bright chestnut brown.