Narrative of the surveying voyages of his majesty's ships Adventure and Beagle (vol.1): between the years 1826 and 1836 : describing their examination of the southern shores of South America, and the Beagles's circumnavigation of the globe

578 HUMMING BIRDS — GEOLOGY. mentioned as illustrative of the mildness of the climate, notwith- standing the lowness of the temperature. One is the comparative warmth of the sea near its surface, between which and the air, I have in the month of June, the middle of the winter season, observed a difference of 30°, upon which occasion the sea was covered with a cloud of steam. The other is, that parrots and humming-birds, generally the inhabitants of warm regions, are very numerous in the southern and western parts of the Strait the former feeding upon the seeds of the Winter's bark, and the latter having been seen by us chirping and sipping the sweets of the Fuchsia and other flowers, after two or three days of con- stant rain, snow, and sleet, during which the thermometer had been at freezing point. We saw them also in the month of May upon the wing, during a snow shower : and they are found in all parts of the south-west and west coasts as far as Valparaiso. I have since been informed that this species is also an inhabitant of Peru ; so that it has a range of more than 41° of latitude, the southern limit being 53 i° south.* Tierra del Fuego is divided by several channels ; a principal one of which is opposite to Cape Froward, and another fronts Port Gallant. The easternmost, called Magdalen, trends in a due south direction for nineteen miles, and separates the clay slate from the more crystalline rocks, which seem to predominate in Clarence Island, and are chiefly of greenstone ; though, at the eastern end, there is much mica slate. At the bottom of Mag- dalen Sound the channel turns sharply to the westward ; and after a course of about forty miles, meets the Barbara Channel, which, as above-mentioned, communicates with the Strait opposite to Port Gallant, and both fall into the sea together. Magdalen Sound and its continuation, Cockburn Channel, are almost free from islands and rocks ; but the Barbara Channel, which separates * This bird, although not rare in several English collections had never been noticed until I forwarded it to England in the early part of the year 1827, when my friend Mr. Vigors described it in the Zoological Journal for the month of November 1827 (vol. iii. p. 432), under the name of Mellisuga Kingii. Shortly afterwards, M. Lesson published it in his Manuel d'Ornithologie (vol. ii. p. 80), as Ornismya sephaniodes, as a discovery belonging to the Coquille's voyage, in the illustrations of which it is figured at plate ."^1