CONTENTS 



Letter of Transmittal iii 



The Board of Regents iv 



Part I. General. 



Economic Importance of the Collembola 3 



General Characters of the Collembola 5 



Relationships of the Collembola 9 



Collecting and Preserving Collembola. . 13 



Literature 15 



Part II. Systematic. 



Terms Used 23 



Keys for the Determination of Orders, Families, Gen- 

 era, etc 25 



Order Collembola 25 



Family Sminthuridae 25 



Genus PAPIRIUS 26 



" SMINTHURUS 27 



Family Entomobryidae 29 



Genus ORCHESELLA 30 



u ISOTOMA 31 



" ENTOMOBRYA 33 



TOMOCERUS 35 



CYPHODEIRUS 35 



SEIRA 35 



" LEPIDOCYRTUS 36 



Family Poduridae 37 



Genus ACHORUTES 38 



PODURA 39 



" XENYLLA 4 



" -FRIESIA 40 



u 

 u 



