. Relics of primeval life, beginning of life in the dawn of geological time. eries, Madoc, I. Transverse section of Worm-burrow — magnified, as a transparent object.(«) Calcareo-silicious rock. (/) Spacefilled with calcareous spar, (r) Sand agglut-inated and stained black. (d\ Sand less agglutinated and uncoloured. 2. Trans-verse section of IVorm-burrow on weathered surface, natural size. 3. The same,magnified. abundant marine life. It is therefore not wonderfulthat we find little evidence of living beings in theHuronian. In Canada I can point to nothing ofthis kind, except a few cylindrical b
. Relics of primeval life, beginning of life in the dawn of geological time. eries, Madoc, I. Transverse section of Worm-burrow — magnified, as a transparent object.(«) Calcareo-silicious rock. (/) Spacefilled with calcareous spar, (r) Sand agglut-inated and stained black. (d\ Sand less agglutinated and uncoloured. 2. Trans-verse section of IVorm-burrow on weathered surface, natural size. 3. The same,magnified. abundant marine life. It is therefore not wonderfulthat we find little evidence of living beings in theHuronian. In Canada I can point to nothing ofthis kind, except a few cylindrical burrows, pro-bably of worms (Fig. 15), and spicules possibly ofsilicious sponges, which occur in nodules of chertin the limestones, traces of laminated forms like 68 RELICS OF PRIMEVAL LIFE Cryptozoon or Eozoon (Fig. 17), and minute car-bonaceous fragments which may be debris of sea-weeds or Zoophytes. In rocks of similar age in theUnited States, Gresley has recently discoveredworm-burrows, and in Brittany there are quartzitebeds in which Barrois and Cayeux believe that. Fig. 16.—Casts of Foraminifera, from the Huronian of Brittany,(After Cayeux.) Compare with Globigerinse on Fig. 12 and Archaeospherinae, Figs. 50-54. they have found tests of Radiolarians, Foraminiferaand spicules of sponges, but their organic nature hasbeen denied by Rauff, of Bonn. The casts of Fora-minifera, however, at least appear to be organic(Fig. 16), and it is quite likely that Cayeux may be
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