154 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 57 



Table of Classification 

 Class Crustacea 

 Sub-Class Branchiopoda 



Order Anostraca Caiman 

 Family Opabinidas, new family- 

 Genus Opahinia, new genus 



Genus Leanchoilia, new genus 



Genus Yohoia, new genus 



Genus Bidentia, new genus 

 Order Notostraca Caiman 

 Family Naraoida2, new family 



Genus Naraoia, new genus 

 Family Burgessidse, new family 



Genus Burgessia, new genus 

 Family (Undetermined) 



Genus Anomalocaris Whiteaves 

 Family Waptidae, new family 



Genus Waptia, new genus 

 Sub-Class Malacostraca 



Order Hymenocarina Clarke 

 Family Hymenocaridae Salter 



Genus Hymenocaris Salter 

 Family (Undetermined) 



Genus Hiirdia, new genus * 



Genus Tuzoia, new genus 



Genus Odaraia, new genus 



Genus Fieldia, new genus 



Genus Carnarvonia, new genus 

 Sub-Class Trilobita 



Order (Undetermined) 

 Family Marrellidae, new family 



Genus Marrella, new genus 

 Family (Undetermined) 



Genus Nathorstia, new genus 

 Order Hypoparia Beecher 

 Family (Undetermined) 



Genus Mollisonia, new genus 



Genus Tontoia, new genus 



^ No attempt has been made to indicate the family relations of the large 

 forms represented by the genera Hurdia, Tuzoia, and Odaraia. With our 

 present knowledge of them they might possibly be referred to the Hymeno- 

 caridae of Salter. 



