1. _Transverse section of Worm-burrow_--magnified, as a transparent object. (_a_) Calcareo-silicious rock. (_b_) Space filled with calcareous spar, (_c_) Sand agglutinated and stained black. (_d_) Sand less agglutinated and uncoloured. 2. Transverse section of Worm-burrow on weathered surface, natural size. 3. The same, magnified.] Such a formation is not likely to afford fossils in any considerable number and variety, even if deposited at a time of abundant marine life. It is therefore not wonderful that we find little evidence of living beings in the Huronian. In Canada I can point to nothing of this kind, except a few cylindrical burrows, probably of worms (Fig. 15), and spicules possibly of silicious sponges, which occur in nodules of chert in the limestones, traces of laminated forms like Cryptozoon or Eozoon (Fig. 17), and minute carbonaceous fragments which may be debris of sea-weeds or Zoophytes. In rocks of similar age in the United States, Gresley has recently discovered worm-burrows, and in Brittany there are quartzite beds in which Barrois and Cayeux believe that they have found tests of Radiolarians, Foraminifera and spicules of sponges, but their organic nature has been denied by Rauff, of Bonn. The casts of Foraminifera, however, at least appear to be organic (Fig. 16), and it is quite likely that Cayeux may be able to verify his Radiolarians and sponges as well. Matthew's observations in New Brunswick in any case establish their probability. Gümbel also recognises a species of Eozoon in the equivalent rocks of Bavaria (see p. 213). [Illustration: Fig. 16.--_Casts of Foraminifera, from the Huronian of Brittany._ (After Cayeux.) Compare with Globigerinæ on Fig. 12 and Archæospherinæ, Figs. 50-54.] [Illustration: Fig. 17.--_Cryptozoon or Eozoon from the Hastings Series, Tudor, Ontario_ (natural size). From a specimen collected by the late Mr. Vennor, and now in the collection of the Geological Survey, Ottawa. (See also Frontispiece and figure of _Eozoon Bavaricum_, p. 213.)] It is evident that here we have approached the limit of the higher forms of marine invertebrate life, having as yet nothing to show except worms and Protozoa. It is to be observed, however, that there may be somewhere Huronian deposits formed in deep and quiet waters, which may give better results, and that the unconformity between the Huronian and overlying Kewenian may indicate a lapse of time, of which monuments may yet be found. The Laurentian.