Page:Walcott Cambrian Geology and Paleontology II.djvu/176

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110
SMITHSONIAN MISCELLANEOUS COLLECTIONS
VOL. 57
Class Gephyrea—Quatrefages 127
Family Ottoidæ, new family 128
Genus Ottoia, new genus 128
Ottoia prolifica, new species 128
Ottoia minor, new species 129
Ottoia tenuis, new species 130
Genus Banffia, new genus 130
Banffia constricta, new species 130
Family Pikaidæ, new family 131
Genus Pikaia, new genus 131
Pikaia gracilens, new species 132
Genus Oesia, new genus 132
Oesia disjuncta, new species 133


ILLUSTRATIONS

PAGE
Plate 18. Miskoia preciosa 134
19. Genera Ottoia, Selkirkia 136
20. Genera Pikaia, Oesia 138
21. Genera Wiwaxia, Banffia 140
22. Genera Worthenella, Amiskwia, Ottoia 142
23. Genera Canadia, Aysheaia 144


INTRODUCTION

This is the third paper on Middle Cambrian fossils from the Burgess shale member of the Stephen formation of British Columbia. The first was on the Merostomata[1] and the second on the Holothurians and Medusæ.[2] We now have for consideration the annelids. As a rule the annelids have been known only by trails and borings in the muds and sands deposited in the various periods between the Pre-Cambrian Algonkian and the present, and only under very exceptional conditions have any traces of the actual animal been preserved. The most noted discoveries are those in the Upper Jurassic Solenhofen lithographic shales of Bavaria and the Eocene shales of Monte Bolca. Another discovery that has long escaped the attention of authors is that made by Dr. E. O. Ulrich and described by him in 1879.[3] These fossils appear to be true segmented Polychætous annelids from the Ordovician shale at Cincinnati, Ohio.


  1. Smithsonian Misc. Coll., Vol. 57, No. 2, 1911.
  2. Idem, No. 3.
  3. Journ. Cincinnati Soc. Nat. Hist., Vol. 1, 1879, pp. 87-91. pl. 4, figs. 1-4.