. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. 140 Dr. H. A. Nicholson on some Fossils them, as might be expected when we consider the number and complexity of the Quebec Graptolites. It would seem, there- fore, that the constant association of these fossils with Grapto- lites (whenever these latter occur in any plenty), and their constant absence from strata in which Graptolites are unknown, constitute extremely strong proofs as to there being a natural connexion between the two sets of organisms. Without entering further
. The Annals and magazine of natural history; zoology, botany, and geology. Natural history; Zoology; Botany; Geology. 140 Dr. H. A. Nicholson on some Fossils them, as might be expected when we consider the number and complexity of the Quebec Graptolites. It would seem, there- fore, that the constant association of these fossils with Grapto- lites (whenever these latter occur in any plenty), and their constant absence from strata in which Graptolites are unknown, constitute extremely strong proofs as to there being a natural connexion between the two sets of organisms. Without entering further into their nature at present, I shall simply describe three Avell-marked forms of these bodies which occur in the shales of the Quebec group, and which differ both from one another and from the forms v/hich are found in the Graptolitiferous rocks of the south of Scotland and the north of England. Daiosoma acuminata^ Nich, Capsule of a long oval shape, having one extremity prolonged gradually, and without any marked line of demarcation, into a long acuminate mucro. The marginal fibre extremely delicate, and not always to be detected. Often showing an impressed line, which proceeds inwards from the mucro to a greater or less distance within the sac. Dimensions variable ; in the Quebec specimens mostly about one fifth of an inch in length by one tenth of an inch at the greatest width ; in English spe- cimens the average dimensions as above, but large examples showing a length of two fifths of an inch by a greatest width of three twentieths of an inch. (Fig. 3, a, a!.) i Fig. 3. 3€). Various forms of Dawsonia : a, Dawsonia acuminata, natural size; a', the same, enlarged; J, D. rotunda, natural size ; i', the same, enlarged; c, D. temmtriuta, natural size ; c', the same, enlarged; rf, rf', another variety of D. teimistriata ; e, f, forms of 7). cumpamilata, enlarged. Dawsonia acuminata is exceedingly abundant in some beds of the Quebec group at Point Ldvis, where it constitutes t
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