PLATE III.--MATURE INSECTS.
Fig. 1, Chloëon; 2, Meloë (after Shuckard); 3, Calepteryx; 4, Sitaris (after Shuckard); 5, Campodea (after Gervais); 6, Acilius; 7, Termes; 8, Stylops (female); 9, Thrips.
PLATE IV. YOUNG FORMS OF THE INSECTS REPRESENTED ON PLATE III.--Fig. 1, Larva of Chloëon; 2, Larva of Meloë (after Chapuis and Candèze); 3, Larva of Calepteryx (after Léon Dufour); 4, Larva of Sitaris; 5, Larva of Campodea; 6, Larva of Acilius; 7, Larva of Termes (after Blanchard); 8, Larva of Stylops; 9, Larva of Thrips.
Ants also keep a variety of beetles and other insects in their nests. That they have some reason for this seems clear, because they readily attack any unwelcome intruder; but what that reason is, we do not yet know. If these insects are to be regarded as the domestic animals of the ants, then we must admit that the ants possess more domestic animals than we do.
Some indeed of these beetles produce a secretion which is licked by the ants like the honeydew; there are others, however, which have not yet been shown to be of any use to the ants, and yet are rarely, if‘ ever, found, excepting in ants' nests.
M. Lespès, who regards these insects as true domestic animals, has recorded[8] some interesting observations on the relations between one of them (Claviger Duvalii) and the ants (Lasius niger) with which it lives. This species of Claviger is never met with except in ants' nests, though on the other hand there are many communities of Lasius which possess none of these beetles; and M. Lespès found that when he placed Clavigers in a nest of ants which had none of their own, the beetles were immediately killed and eaten, the ants themselves being on the other hand kindly received by other communities of the same species. He concludes from these observations that some communities of ants are more advanced in civilization than others; the suggestion is no doubt ingenious, and the fact curiously resembles the experience of navigators who have endeavoured to introduce domestic animals among barbarous tribes; but M. Lepès has not yet, so far as I am aware, published the details of his observations, without which it is impossible to form a decided opinion. I have sometimes wondered whether the ants have any feeling of reverence for these beetles; but the whole subject is as yet very obscure, and would well repay careful study.
The order Strepsiptera are a small, but very remarkable group of insects, parasitic on bees and wasps. The larva (Pl. [IV.], Fig. 8) is minute, six-legged, and very active; it passes through its transformations within the body of the bee or wasp. The male and female are very dissimilar. The males are minute, very active, short-lived, and excitable, with one pair of large membranous wings. The females (Pl. [III.], Fig. 8), on the contrary, are almost motionless, and shaped very much like a bottle; they never quit the body of the bee, but only thrust out the top of the bottle between the abdominal rings of the bee.