Note 6 — CHAP. IV. OF THE RELATION BETWEEN ANTS.

That ants will occasionally avail themselves of the heat supplied by other sources besides the sun, is sufficiently evident from what follows: “M. Reaumur, in refuting the common notion of ants being injurious to bees, tells us, that societies of the former often saved themselves the trouble of removing the larvæ, &c. from place to place, by establishing their colonies between the exterior wooden shutters and panes of his glass hives, where, owing to the latter substance being a tolerably good conductor for heat, their progeny was, at all times, and without any necessity of changing their situation, in a constant, equable, and sufficient temperature. Bonnet observed the same fact. He found that a society of ants had piled up their young to the height of several inches, between the flannel-lined case of his glass hives and the glass. When disturbed they ran away with them, but always replaced them. I am persuaded that, after duly considering these facts, you will agree with me that it is impossible consistently to refer them to instinct, or to account for them without supposing some stray ant, that had insinuated herself into this tropical crevice, first to have been struck with the thought of what a prodigious saving of labour and anxiety would occur to her compatriots by establishing their society here; that she had communicated her ideas to them; and that they had resolved upon an emigration to this newly discovered country—this Madeira of ants, whose genial clime presented advantages which no other situation could offer. Neither instinct, nor any conceivable modification of instinct, could have taught the ants to avail themselves of a good fortune, which, but for the invention of glass hives, would never have offered itself to a generation of these insects since the creation; for there is nothing analagous in nature to the constant and equable warmth of such a situation, the heat of any accidental mass of fermenting materials soon ceasing, and no heat being given out from a society of bees when lodged in a hollow tree, their natural residence. The conclusion, then, seems irresistible, that reason must have been their guide, inducing a departure from their natural instinct; as extraordinary as would be that of a hen which should lay her eggs in a hot-bed, and cease to sit upon them.”—Introduction to Entomology, by Kirby and Spence, Vol. II. p. 518.—T.