CONTENTS. 



Page. 



Introduction 1 



Preparation qnd scope of the work 1 



Acknowledgments 2 



Object and methods of study 4 



( 'alalogne of papers of American Early Tertiary Bryozoa 7 



Synonymic references 10 



Reference of previously described North American Early Tertiary Bryozoa 10 



Geologic tables of Mesozoic and Cenozoic formations 12 



Subdivisions of European and South American Mesozoic and Cenozoic rocks 13 



List of Mesozoic and Cenozoic formation names 14 



List of localities with formations and station numbers 15 



Lists showing geographic and geologic distribution 17 



Lowest Eocene 17 



Midwayan bryozoa 17 



\Vilcoxian (Boshi) 19 



Claibornian bryozoa 19 



Jacksonian bryozoa 20 



Vicksburgian bryozoa 34 



General description of the lyozoa 39 



( 'lassification 40 



Structure of the Cheilostomata 41 



General consideration of the Cheilostomata 46 



Endocyst and ectocyst 46 



Zoarial budding and formation of skeleton 46 



Olocyst 47 



Tremocyst 48 



Tubules 49 



Pleurocyst 50 



Septulae and dietellae '. 51 



Function of reproduction 53 



Larva 53 



O vicells :,:\ 



Nonovicelled zooecia 53 



Nature of the ovicells 54 



Structure of the ovicells 55 



Passage of the eggs 56 



Fixation of the larva 56 



Hydrostatic functions 57 



Zooecial hydrostatic relations 57 



Operculum 



Ascopore 60 



Hypostege 60 



Zoarial hydrostatic system 60 



Use of the vibracula 61 



Functions of relation 61 



Avicularia 61 



Frontal or immersed avicularia 64 



Interzooecial avicularia 64 



v 



