■28 The Ohio Journal of Science [Vol. XXI, No. 1, 



classification is due to two things: 1, The attempt to show 

 phylogeny by venation which is hopeless because of the numer- 

 ous convergences; and 2, The failure to recognize that there 

 are four major series and not, three as outlined by de Selys. 

 These are: 



1. The Argia series with long leg spines, the most general- 

 ized members of which are Onychargia and Diargia and which 

 has developed through Argia into the giant Hyponeiira. 



2. The CcENAGRiON-PsEUDOGRiON. These have short tibial 

 spines, females without a vulvar spine and have a rounded 

 frons. These start with such genera as Erythromma and Cercion 

 and end in the large modern genera mentioned above. 



3. The Enallagma-Acanthagrion series. This series is 

 characterized by short tibial spines, rounded frons, females with 

 a vulvar spine. This splits into two series on the nature of the 

 male appendages. 



(a) The Enallagma series with forked appendages. 



(b) The Acanthagrion series with the dorsal appendages 

 slanting downward. 



4. The Nehalennia-Telebasis series. These have short 

 tibial spines, females without vulvar spine, and have an angulate 

 frons. This is the series that has been heretofore mixed through 

 the first three series with interminable confusion. The penes are 

 characteristic in many of the species of this series which indicates 

 its validity. This falls into two distinct series. 



(a) The Chromagrion-Nehallenia-Teinobasis series with 

 appendages that have a large basal spine. 



(b) The Ceriagrion-Telebasis-Metaleptobasis series in 

 which the appendages do not have a well developed basal spine. 



The curious Argiallagma of Florida and Cuba has characters 

 of series 1, 3 and 4 and appears to be a very ancient insect. 



EXPLANATION OF PLATES I, II AND III. 



LESTINiE — 



Figs. 1-2. Megalestes major Selys. Kooloo, Carleton. 



Figs. 3-4. Archileslis grandis (Rambur). Tucson, Ariz. 



Figs. 5-6. Lestes disjunctus Selys. Bluffton, Ind. 



Figs. 7-8. Ausfrolestes cingtilatus (Burm.) Victoria, Australia. 



Fig. 9. Austrolestes temiissimus Tillyard. Cooktown, Australia. 



Figs. 10-11. Chlorolestes conspicua Selys. (S.Africa). 



Figs. 12-13. Chlorolestes fessallata (Burm.). (S.Africa). 



Figs. 14-15. Synlestes weyersi Selys. Victoria, Australia. 



