TABLE OF CONTEXTS. XV 



525. AVhat is meant by the term Azoic, ami what rocks may be included under 

 that designation, 526, 527. How FosTKU and Whitney used tlie term Azoic, 

 527. The condition of things in regard to the propriety of the use of that term, 

 527. Injustice done by Logan in his introduction of tlie name Laurentian, 

 527, 528. Discussion of the question whether the term Archaean ought to replace 

 that of Azoic, 528. Examination of the Eozoon question, 528-538; first announce- 

 ment of its existence by Logax, in 1858, 528 ; Dawson, in 1864, announces 

 that it belongs to the Rhizopods, and that its discovery will be " one of the bright- 

 est gems in the scientific crown of the Geological Survey of Canada," 529; further 

 investigation of the Eozoon by Caupenter, and its recognition by him as a 

 Foraminifer, 529; his authority insures its general recognition as the earliest 

 known representative of life, 529; opposition, however, begins to manifest itself, 

 529; gradual accumulation of an eozoonal literature, but general acceptance of 

 the Eozoon Canadcnse, 530 ; diflBculty in the way of proving that it was not 

 organic, 530 ; how MiiBius overcame this diflSculty, 530, 531 ; his results, 

 and the characterization of them by Zittel and F. Hoemeu, 531; Leidy's views, 

 531; our own investigations into the character of the " Eozoonal limestones " of 

 Eastern Massachusetts, 532-534. Prevalent tendency among palaeontologists, at 

 the present time, to find traces of organic life in all kinds of rocks. Such a.s 

 granite, lava, and even in slag — this accounted for, 534. Some evidence in re- 

 gard to the ability of Carpenter and Daavson to distinguish minerals from 

 fossils, 534-537. Extraordinary discoveries of Otto Hahn, and their bearing 

 on the Eozoon question, 537, 538. Question discussed whether the existence of 

 limestone and graphite is a ^;roof of the presence of life at the time of their forma- 

 tion, 538-544. Bischof's \iews in regard to the existence of carbon during the 

 primeval epoch, 538 ; his evidence controverted, 538-543; graphite in cast-iron, 

 538; in the crystalline rocks, 539; not formed as coal has been, 540; plumbago 

 not always graphite, 540; the ai-titicial production of graphite, and of the dia- 

 mond, 540 ; graphite formed in the Le Blanc process, 541; Biscuof's ideas in 

 regard to the mode of occurrence of the diamond shown to be iucoiTect, 541, 

 542; how it does occur, in connection with gold, 542; in South Africa, in vol- 

 canic rocks, 542, 543; some facts in regard to the peculiar circumstances under 

 which the diamond must have been formed, 543. Examination of the cuiTent 

 idea that the presence of carbonate of lime is proof of the existence of life at the 

 time this was formed, 543, 544. Similar inquiry in regard to iron, 544 ; in 

 regard to sulphur, 544, 545; phosphoric acid, 545. No encouragement given, 

 bj' the investigations of the past half-century, to the idea that below the 

 Primordial or Potsdam zone there is another series of fossiliferous rocks, 545. 

 The wish father to the thought, 545, 546; Lyell "revels with delight" 

 (fide ilurchison) at the discovery of the Eozoon, 545. Difficulty in which evo- 

 lutionists are placed by its adoption, 546 ; F. Roemer's statement of the case 

 recommended for consideration, 546. Remarkable result of pal^ontological 

 investigations — one and the same fauna over the whole globe during the Pri- 

 mordial epoch, 546. Inferences with regard to the azoic character of the Azoic 

 series, 546. Inquiry into Dana's use of his tenn Archiean, 547-550; he includes 

 under that designation rocks of different ages, both fossiliferous and non- 

 fossiliferous, 547 ; the importance of recognizing in our nomenclature the epoch 

 of the first introduction of life u^jou the globe, 547. Dana believes that a part 



