. The dawn of life [microform] : being the history of the oldest known fossil remains, and their relations to geological time, and to the development of the animal kingdom. Paleontology; Life; Paléontologie; Vie. JT. i;iji!l:ni 1 I 1 I I. i ai\ 194 THE DAWN OF LIFE. have been prepared. I have examined these with care, and am prepared to aflBrm that the chambers in these specimens are filled with a dark-coloured limestone not more crystalline than is usual in the Silurian rocks, and that the chamber- walls are composed of carbonate of lime, with the canals filled with the same material, except
. The dawn of life [microform] : being the history of the oldest known fossil remains, and their relations to geological time, and to the development of the animal kingdom. Paleontology; Life; Paléontologie; Vie. JT. i;iji!l:ni 1 I 1 I I. i ai\ 194 THE DAWN OF LIFE. have been prepared. I have examined these with care, and am prepared to aflBrm that the chambers in these specimens are filled with a dark-coloured limestone not more crystalline than is usual in the Silurian rocks, and that the chamber- walls are composed of carbonate of lime, with the canals filled with the same material, except where the limestone filling the chambers has penetrated into parts of the larger ones. I should add that the stratigraphical researches of Mr. Vennor, of the Canadian Survey, have rendered it probable that the beds containing these fossils, though unconformably under- lying the Lower Silurian, overlie the Lower Laureutian of the locality, and are, therefore, probably Upper Laurentian, or perhaps Huronian, so that the Tudor specimens may approach in age to Giimbel's Eozoon Bavaricum.* Further, the authors of the paper have no right to object to our regarding the laminated specimen as *' typical" Eozoon. If the question were as to typical ophite the case would be different; but the question actually is as to certain well-defined forms which we regard as fossils, and allege to have organic structure on the small scale, as well as lamination on the large scale. "We profess to account for the acervuline forms by the irregular growth at the surface of the organisms, and by the breaking of them into fragments confusedly intermingled in great thicknesses of limestone, just as fragments of corals occur in Palaeozoic limestones ; but we are under no obligation to accept irregular or disintegrated specimens as typical; and when objectors reason from these fragments, we have a right to point to the more perfect exam^)les. It would be easy to explain the loose cells of Tetradium
Size: 1390px × 1799px
Photo credit: © Library Book Collection / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1870, booksubjectpaleontology, bookyea
