Mr. Edwards has meanwhile published these communications in full; cf. ‘On the length of life of Butterflies,’ Canadian Entomologist, 1881, p. 205. Footnote 12: When no authority is given, the observations are my own. Footnote 13: In the paper quoted above, Edwards, after weighing all the evidence, reduces the length of life from three to four weeks. Footnote 14: ‘Entomolog. Mag.,’ vol. i. p. 527, 1823. Footnote 15: Ibid. Footnote 16: Ibid. Footnote 17: ‘Recherches sur les mœurs des Fourmis indigènes,’ Genève, 1810. Footnote 18: These two female ants were still alive on the 25th of September following Sir John Lubbock’s letter, so that they live at least seven years. Cf. ‘Observations on Ants, Bees, and Wasps,’ Part VIII. p. 385; Linn. Soc. Journ. Zool., vol. xv. 1881. [Sir John Lubbock has kindly given me further information upon the duration of life of these two queen ants. Since the receipt of his letter, the facts have been published in the Journal of the Linnean Society (Zoology), vol. xx. p. 133. I quote in full the passage which refers to these ants:— ‘Longevity.—It may be remembered that my nests have enabled me to keep ants under observation for long periods, and that I have identified workers of _Lasius niger_ and _Formica fusca_ which were at least seven years old, and two queens of _Formica fusca_ which have lived with me ever since December 1874. One of these queens, after ailing for some days, died on the 30th July, 1887. She must then have been more than thirteen years old. I was at first afraid that the other one might be affected by the death of her companion. She lived, however, until the 8th August, 1888, when she must have been nearly fifteen years old, and is therefore by far the oldest insect on record. ‘Moreover, what is very extraordinary, she continued to lay fertile eggs. This remarkable fact is most interesting from a physiological point of view. Fertilization took place in 1874 at the latest. There has been no male in the nest since then, and, moreover, it is, I believe, well established that queen ants and queen bees are fertilized once for all. Hence the spermatozoa of 1874 must have retained their life and energy for thirteen years, a fact, I believe, unparalleled in physiology.’ * * * * * ‘I had another queen of _Formica fusca_ which lived to be thirteen years old, and I have now a queen of _Lasius niger_ which is more than nine years old, and still lays fertile eggs, which produce female ants.’