Proceedings of the Academy of Natural Sciences of Philadelphia

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Academy of Natural Sciences of Philadelphia, 1883

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Page 148 - Robinson was elected a member of the Council, to fill the vacancy caused by the election of the Rev.
Page 204 - Five of the genera are peculiar to the Secondary. An Ammonite ranges entirely through the group to the top of the highest fossiliferous strata. The genera Perissolax, Gyrodes, Margaritella, and the sub-genus Anchura, of the genus Aporrhais, are all recognized as strictly characteristic of the Cretaceous ; so much so, that the presence of a single undoubted representative of either of these genera would be strong presumptive evidence of the Cretaceous age of any rocks in which it might be found.
Page 115 - It was one of the most ancient as well as one of the most interesting places in sacred record.
Page 239 - The body terminated in a caruncular point which, with the position of the two hind-legs, made a tridentate obstruction to the sand brought down by the retreating wave, and the water passing .around the points made the three toe-like grooves which resembled a bird's foot from one and a half to two inches long. The creatures in their scrambles for protection beneath the sand, managed to keep at fair distances from each other, and hence there was considerable regularity in the tracks as if they had...
Page 339 - The beds of argillaceous iron-ore, which spread so widely through New York and some of the other States west, could not have been formed in an open sea; for clayey iron-deposits do not accumulate under such circumstances. They are proof of extensive marshes, and, therefore, of land near the sea-level. The few fragments of Crinoids and shells found in these beds are evidence that they were, in part at least, salt-water marshes, and that the tides sometimes reached them.
Page 263 - orange-ant feeders' are provided with pig or goat bladders, which are baited inside with lard. The orifices of these they apply to the entrance of nests, when the ants enter the bags and become a marketable commodity at the orangeries.
Page 214 - I was not able to find a single cretaceous fossil, nor even any true cretaceous generic forms, in the entire formation ; and I am altogether of the opinion expressed by Mr. Conrad, many years before Mr. Gabb, in volume 5, of Pacific Railroad Explorations, pages 318, 320, et.
Page 237 - Jersey, where they were very abundant, and had proved a great pest in the cultivation of tobacco. The worms collected presented a number of well-marked varieties, which were supposed to be all of the same species. The principal ones were indicated as follows : 1. Pea-green or...
Page 260 - One of oval form measured 1 mm. long by 0.75 mm. broad. The smaller ones measured 0.75 mm. in diameter. After another day they appeared in good condition, but the rays were contracted so as to be about half the original length, and many had a minute granular ball at the end, apparently effete matter thrown off from them. At this time the animalcules were returned to the aquarium.
Page 345 - Origin of sedias to whether they were originally deposited as such, or in some other tit(?s- — form, and afterwards altered to magnetite. It seems possible that, in some cases, beds may have been formed by the accumulation of iron sands, just as they are forming in the Gulf of St. Lawrence to-day, the material being derived from the disintegration of pre-existing crystalline rocks.

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