CONTENTS 



PAGE 



Introduction i 



Description of genera and species 2 



Komaspidae Kobayashi 2 



Chariocephalus Hall 4 



Irvingella Ulrich and Resser 13 



Parairvingella Kobayashi 25 



Drumaspis, new genus 28 



Unclassified genera 35 



Cheilocephalns Berkey 35 



Cholopilus Raymond 36 



Caiyptonima, new genus 37 



Illaenurus Hall 38 



Platycolpus Raymond 40 



Enontioura, new genus 42 



Macclloura Resser 43 



Arapahoia Miller 43 



Plethomctopus Ulrich 47 



Kingstonia VValcott 47 



Byniunia Walcott 52 



BynumicUa, new genus 57 



Bynumina, new genus 58 



Stenopilns Raymond 59 



Blountia Walcott 60 



Blountiella Resser 61 



Ellipsocephaloides Kobayashi 62 



MaryviUia Walcott 67 



Meteoraspis Resser 72 



Coosia Walcott 73 



Coosella Lochman 75 



Ptcroccphalina Resser 76 



Burnetidae, new family 79 



Burnetia Walcott 80 



Iddingsia Walcott 85 



Berkeia Resser 90 



Unclassified genera 94 



Elvinia Walcott 94 



Taenicephalus Ulrich and Resser 99 



Talbotina Lochman 107 



Explanation of plates 109 



Index 131 



iii 



