Note 11 — Chapter VI · TRACHYTE AND BASALT.—DISTRIBUTION OF VOLCANIC ISLES.

This is stated on the authority of Count V. de Bedemar, with respect to Flores and Graciosa (Charlsworth, “Magazine of Nat. Hist.,” vol. i, p. 557). St. Maria has no volcanic rock, according to Captain Boyd (Von Buch “Descript.,” p. 365). Chatham Island has been described by Dr. Dieffenbach in the “Geographical Journal,” 1841, p. 201. As yet we have received only imperfect notices on Kerguelen Land, from the Antarctic Expedition.