XI.—On the Presence of Formic Acid in the Stinging Hairs of the Nettle

^{page 137 note *} J. Prakt. Chem., vol. xlviii (1849), p. 191.

^{page 137 note †} See, in particular, investigations by Bergmann (Bot. Zeit., vol. xl (1882), p. 731, etc.), who gives a review of the earlier literature.

^{page 137 note ‡} Compare Shannon, Journ. Indust. Engin. Chem., vol. iv (1912), p. 526.

^{page 138 note *} Sitzungsber. der Akad. der Wissenschaft. Wien, vol. xciii, 1. (1886), p. 130.

^{page 138 note †} Proc. Liverpool Biolog. Soc., vol. iv (1890), p. 93.

^{page 138 note ‡} Proc. Linn. Soc. N.S. Wales, vol. xxxi (1906), p. 530.

^{page 139 note *} Loc. cit., p. 132.

^{page 140 note *} See Groth, Chemische Krystallographie, iii Teil (1910), p. 17.

^{page 141 note *} Chemische Krystallographie, iii Teil (1910), p. 15.

^{page 141 note †} Schweigger's Annalen, vol. iv (1812), pp. 36, 38, and figure. (It is to be noted that Bernhardi figures barium formate, but that the habit of lead formate is in some cases identical with that of barium formate. See Groth, loc. cit., p. 17.)

^{page 142 note *} Compare Lieben, Monatshefte, vol. xix (1898), 352.

^{page 142 note †} Vide ante, p. 138.