Bulletin of the United States Geological and Geographical Survey of the Territories, Volume 5


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Pagina 11 - ... sexual individuals, the females of which so often perish while yet covering their solitary winter eggs. I have not been able to prove absolutely that there are two broods of the gall-making female, and my observations all tend to the conclusion that no galls are formed except by the stem-mother that hatches from the impregnated egg.
Pagina 6 - ... during the latter part of June and the early part of July, but leaves the latter part of the summer poorly occupied.
Pagina 10 - They doubtless insert their beaks in various portions of the buds or expanding leaves ere settling, since, before the gall begins to form, the little architect has generally obtained twice the size it had when first hatched. By the middle of April, in the latitude of Saint Louis, the galls generally begin to show, at first as slight elongate ridges on the upper surface, with corresponding closed depressions on the lower surface. Upon drawing apart the lips of the wrinkle beneath, at this stage of...
Pagina 242 - L'Amérique Méridionale, par Don Félix de Azara, Commissaire et Commandant des limites espagnoles dans le Paraguay depuis 1781 jusqu'en 1801 ; Contenant la description géographique, politique et civile du Paraguay et de la rivière de La Plata ; l'histoire de la découverte et de la conquête de...
Pagina 5 - Having attained maturity, she commenees peopling her pseudo-gall with young at the rate of about one every six or seven hours, according to temperature, increasing in bulk and prolificacy from day to day, until by the early part of May, in the latitude of Saint Louis, she has attained her fullest development, and soon perishes. She may attain to nearly four millimetres in length, and, with greatly swollen body, be almost as wide (Fig.
Pagina 124 - ... the bleached trunks of the ancient forests. In the steeper middle portion of the mountain face, rows of upright trunks stand out on the ledges like the. columns of a ruined temple. On the more gentle, slopes farther down, but where it is still too steep to support vegetation, save a few pines, the petrified trunks fairly cover the surface, and were at first supposed by us to be the shattered remains of a recent forest.
Pagina 5 - ... b). Her immediate issue, or the second generation, are like her in many respects, but never grow to be quite so large. The individuals of this generation soon accumulate in great numbers around her, and in their turn commence to bring forth young, some remaining within the original curl, others scattering to found new colonies. Their issue, or the third generation, show certain marked structural differences from the first (see description), and are destined to become winged. "During most of the...
Pagina 148 - Thesaurus Devonico-Carboniferus : the Flora and Fauna of the Devonian and Carboniferous Periods, the Genera and Species arranged in Tabular Form, showing their Horizons, Recurrences, Localities, and other Facts : with Large Addenda from Recent Acquisitions, Lon., 1S7!*, 4to.
Pagina 193 - ... that; this vertical dislocation took place after the whole area was compressed into a great region of anticlinals with intermediate synclinals. In other words, it was a region of enormous and complicated folds, riven in later time by a vast series of vertical displacements, which have partly cleft the anticlinals down through their geological axes, and partly cut the old folds diagonally or perpendicularly to their axes.
Pagina 6 - While the individuals thus wandering are mostly the younger ones, the migrating instinct seems sometimes to possess individuals of all ages, especially where the tree is badly affected; and that they perish is proved by the mass of dead lice which in such a case may be found around the base of a tree. So far as I have been able to learn by confining specimens of the fifth generation, which is very similar to the fourth, but with shorter pronrascis, the fifth reproduces like the fourth without acquiring...

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