CONTENTS. 
Page. 
Introduction 1 
General distribution of Silurian Bryozoa 2 
General discussion of the Rochester shale and its Bryozoan fauna 2 
Collecting in the Rochester shale. 4 
Correlation. 5 
Bibliography 8 
Descriptions of genera and species 11 
Order Ctenostomata. 11 
Rhopalonariidse 11 
Vinellidse 12 
Ascodictyonidae. 14 
Order Cyclostomata 14 
Diastoporidae 14 
Elntalophorida 1 17 
Ceramoporida> 18 
Fistuliporidse 22 
Order Trepostomata 26 
Monticuliporidae 26 
Heterotrypidae 27 
BatostomellidsB 28 
Amplexoporidai 37 
Constellariidae 37 
Calloporida^ 40 
Trematoporidas. 43 
Order Cryptostomata. 48 
Phylloporinida' 48 
Fenestellidae 50 
Ptilodictyonidse 55 
Stictoporellidse 57 
Rhinidictyonidse 57 
Rhabdomesontidae 58 
Arthrostylidffi 58 
Rhinoporidffi r 59 
Synonymic list of species 63 
Plates 67 
Index 135 
in 
