Proceedings of the Boston Society of Natural History, Volumen2

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Boston Society of Natural History., 1848
 

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Página 85 - ... so in length, with only, now and then, traces of the bark remaining on the wood. The wood was not at all fossilized, and was but slightly decayed. From the appearance of the branchlets examined, Prof. Gray inferred that they belonged to some coniferous tree or shrub, and, probably, to a kind of spruce or fir, rather than to a true pine. This inference was borne out by the examination of thin slices of the wood by the microscope. The woody fibre was very beautifully and distinctly marked with...
Página 36 - Nutt.) considered as an Echinocactus by Messrs. Torrey and Gray, in their important work on the North American plants : — " This difference of opinion arose probably from Nuttall's description stating that the flowers proceeded from the upper clusters of spines, whereas the flowers of Melocactus proceed from the woolly head characteristic of this genus, in which they are usually imbedded. But Nuttall also states that the fruit is smooth ; this is a character of Melocactus, the fruit of Echinocactus...
Página 179 - ... only. This agrees with the results of other modes of trial in indicating that the latter period is sufficient for the complete preparation of the cotton, when the acids are of full strength. In all the specimens there are some filaments so nearly destitute of polarizing power as to be scarcely visible on the black ground, but none have been found entirely without action. When the polarizing and analyzing prisms are in such a position as to give a bright field, a portion of the fibres becomes...
Página 85 - Gray was induced to examine the substance brought to him. The wood evidently consisted of branchlets of one, two, and three years old, broken, quite uniformly, into bits of half an inch or so in length, with only now and then traces of the bark remaining on the wood. The wood was not at all fossilized, and was but slightly decayed. From the appearance of the branchlets examined, Professor * Final Report on the Geology of Massachusetts, p.
Página 157 - College, and was discovered in a swamp on the farm of Gen. WH Adams, of Clyde. The situation in which it was found is an elevated plateau or level tract of land, a portion only of which would be denominated a swamp, though the whole surface is covered with a peaty soil which supports a heavy growth of elm, hemlock and ash, with some maple and beech. This elevated ground is the summit level, from which the waters flow in opposite directions, into Lake Ontario on the north, and into the Clyde river,...
Página 179 - Gun-Cotton ; by Dr. BACON, (Proc. Boston Soc. Nat. Hist., Feb., 1847, p. 195.) — Specimens of the cotton, before and after preparation, were put up in Canada balsam on slips of glass, and covered by very thin glass. When viewed by transmitted light, with powers from 150 to 800, many of the fibres of the gun-cotton appear thickened, but no other change can be perceived on comparison with the unprepared article.
Página 84 - ... are, in our opinion, clearly mechanical, and cannot be connected with structural condition." — American Journal of Science, Literature, and Arts, vol. iii., p. 433. 2. Food of the Mastodon. — (Proc. Bost, Nat. Hist. Soc.J — Professor Gray stated, that there had been recently placed in his hands specimens of earthy matter, filled with finely broken fragments of branches of trees, which were said to have been found occupying the place of the stomach in the skeleton of the mastodon exhumed...
Página 12 - Soc., ii, 1845, p. 20. Shell sinistral, acuminate-conical, light brown, or white, with beautiful, narrow, dark brown bands, more or less numerous, imperforate; whorls 6, convex; aperture semilunate: lip reflected. Average length i in., diam. 1-2 in. Hab. Waianae, Oahu.
Página 179 - Gun-cotton prepared by Dr. Jackson by immersion for twelve and for eighteen hours in the strongest acids, has not lost its polarizing power in any appreciably greater degree than after an immersion of three minutes only. This agrees with the results of other modes of trial in indicating that the latter...
Página 163 - Annales des sciences physiques et naturelles d'Agriculture et d'Industrie, publiees par la societe royale d'Agriculture etc.

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