could keep them in life and health for months if I gave them a slave for an hour or two in a week to clean and feed them. 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 honey-dew; 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. Lespès 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. [Illustration: 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_.] [Illustration: 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_.]