2 University of Michigan 



properly 1 found it necessary to study carefully the smaller 

 species of the genus, heretofore known as oniata and auianda. 

 The larger species, eponina, elisa, fasciata and monomelaena, 

 seem well enough known, but they are included briefly in the 

 following key for the sake of completeness. The smaller spe- 

 cies are treated in more detail, for this study has shown thai 

 no less than three species have been included under the name 

 ornata. 



In addition to specimens collected by Jesse H. Williamson 

 I have seen specimens from the following collections : the 

 Academy of Natural Sciences, abbreviated A. N. S. in the 

 text, through the kindness of Dr. Calvert; the Museum ot 

 Comparative Zoology, abbreviated M. C. Z. in the text, through 

 the kindness of ]\Ir. Banks ; the United States National 

 Museum, abbreviated U. S. N. M. in the text, through the 

 kindness of Miss Currie; Ohio State University, abbreviated 



0. S. U. in the text, through the kindness of Dr. Kennedy ; 

 and the private collections of Mr. Davis, abbreviated W. T. D. 

 in the text, and Dr. Ris, abbreviated Ris in the text. Speci- 

 mens in my collection are indicated by the abbreviation E- 

 B. W. Mr. Davis kindly gave me the male and female of 

 Celithemis niartha, which I have designated as type and allo- 

 type. To Drs. Calvert and Ris I am indebted for suggestions 

 and advice received during the course of this study. The wing 

 photographs for the two plates were made by Miss Mina L. 

 Win slow. 



Key to the Species of Celithemis 



1. Wings with postnodal markings. Rs and Rspl separated by 



two cell rows or at least a few double cells ' 2. 



i'. Wings without postnodal markings. Rs and Rspl separated 



by a single cell row with very rarely a single double cell. 5. 

 2(1). Wing membrane yellow to orange, a band of darker color 



across the wing just before the stigma; other wing mark- 



