43 ENTOMOLOGICAL NEWS. [Nov., '08 



M 4 and Cu j in front wing widely divergent, Cu l strongly curved. 

 Group V. 



2. M 3 and M 4 in front wing distinctly divergent. Group III. 

 M 3 and M 4 in front wing convergent or only slightly divergent. 



Groups I, II, IV and V. 



3. Anal loop long, apex widened. Groups I and II. 



Anal loop long, apex rounded, not widened. Groups III and IV 



(obscured in Gomphomacromia and Macromidia). 

 Anal loop rounded. Group V. 



4. Proximal angle of the subtriangle in front wing proximal to, on 



level of, or only slightly beyond arculus. Groups I, II and III. 

 Proximal angle of the subtriangle in front wing distal to the 

 level of the arculus by at least the length of the anterior side 

 of the subtriangle. Groups IV and V. (In Group IV the 

 postanal cell* forms more of the posterior side of the sub- 

 triangle than the cell just proximal to the postanal cell : in 

 Group V, excepting in Phyllomacromia where they are about 

 equal, the postanal cell is much the shorter). 



5. In front wing the postanal cell* divided (2-celled). Groups I 

 and II. 



In front wing the postanal cell* undivided. Groups III, IV 

 and V. 



6. Proximal side of triangle in hind wing on level of or proximal to 



arculus. Groups I and II. 

 Proximal side of triangle in hind wing distal to arculus by less 



than length of arculus. Group III. 

 Proximal side of triangle in hind wing distal to arculus by at 



least the length of arculus. Groups IV and V. 



The consideration of these characters and the resulting 

 groupings makes it impossible to reduce the sub-family to a 

 smaller number of co-ordinate sub-groups than five. The 

 stalking or distinct origin of Mi_ 3 and M 4 at the arculus 

 has not been used because of its indefinite character in many 

 cases. The origin is generally distinct in Group I and in 

 Neurocordulia and O.vygastra and stalked in all others reaching 

 the extreme development in Phyllomacromia, Didymops and 

 Idiony.v. Other characters not here mentioned are available 

 for defining groups or genera. For example. Group III has 

 3-5 cross- veins between Mi_ 3 and M4 in front wing and 2 in 



* Postanal cell a small distinct area in the front wing posterior to 

 the subtriangle, homologous with the anal loop of the hind wing in 

 the Cordulinae. 



