BY R. J. TILLYARD. 329 



parallel; head with a prominent pyramidal frontal horn; legs 

 long and spider-like. 



Imagines with a compact anal loop, very little, if at all, longer 

 than wide; triangle of hindwiug never retracted towards arculus; 



basilar space always free. Large insects of strong flight 



Group Macroinina. 



iii. Larvae with elongate-oval body, very villose; wing-cases 

 strongly divergent, head square in front, with eyes projecting 

 from antero-lateral angles; legs short, thick, hairy. 



Imagines with anal loop never as long as wide; basilar space 



always reticulated. Insects of rather weak flight 



Group Synthemina. 



Group i. contains over eighty species; Group ii., nearly fifty; 

 and Group iii., only fifteen. But it is inevitable, in any attempt 

 of this kind, that the most highly developed and successful forms 

 should far outnumber the members of a more archaic group. I 

 do not say, however, that we should rest content with Group i., 

 as it now stands. There may be lines of division of equal value 

 to the others still to be found in that group. In particular, a 

 careful study of the life-histor}' of Cordulephija is necessary 

 before we can be content to leave it in the same group as insects 

 of a vei-y different type. 



To turn now to the study of the Group Synlhemina, consisting 

 of the fifteen species of the genus Syntliemis. Various authors 

 have pointed out the need of some subdivision of the genus, but 

 the attempts made were only tentative, mainly from lack of 

 material to study the group as a whole. Prof. Forster, when 

 describing his new species, S. primigenia from New Guinea, 

 noticed the remarkable difference in the female sex-organs of 

 this species and those of S. brevistyla. Apparently he had no 

 knowledge of the type *S'. etistalacta, However, lie suggests a 

 subdivision into two genera as follows : — 



5. Without ovipositor and conspicuous appendages : c<-10 lying 



in one straight line; 8 clipped off straight behind. ... 



Eusynthemis {S, brevistyla). 



