Vol. xxiv] ENTOMOLOGICAL NEWS 259 



In the figures accompanying this paper, the medio-anal link 

 is labeled MA at either extremity. Thus in Figs. 5 and 6 

 MA alone does not form the distal end of the subquadrangle ; 

 and in Figs. 8, 9 and 10 MA really does not link M with A, 

 though I believe the use of the term in these three cases will 

 be found desirable. However, this is one of the purposes of 

 this paper, to bring out the opinions of others on what terms 

 and expressions are most desirable in these parts in Agrionine 

 wings. In the ten figures, the first two show Calopterygine 

 wings which, in the relations of MA, show a generalized struc- 

 ture. From this condition two distinct evolutionary lines ex- 

 ist, I believe, in Agrioninae (sens lat). In one case MA is 

 the center of evolutionary activity, at first little differentiated 

 from the cross-veins which follow it, set at nearly right angles 

 against M/j., with Cu2 appearing as a continuation of A. 

 Figures 4, 5 and 6 show a rapid change in these characters, 

 MA and M4 forming first a symmetrical fork and then in 

 Fig. 6 MA appears as a continuation of the basal part of M4, 

 while bracing takes place posterior to MA, and A and Cu2 

 are no longer in the same line. The other line of evolution 

 is shown in Figs. 7, 8, 9 and 10. Here MA undergoes no 

 changes except those involved in the reduction of the posterior 

 wing area. In Fig. 7, A is continued to MA, and Cu2 beyond 

 MA is present as a short spur. When, as in Figs. 8, 9 and 

 10, Cu2 is confined to MA, A passes CA (cubital-anal cross- 

 vein) to return to the wing margin (Fig. 8), to switch against 

 the quadrangle (Fig. 9), or terminates at CA (Fig. 10), in 

 which last case wing reduction reaches its maximum. 



EXPLANATION OF FIGURES. 



Figure i. Typical Calopterygine wing-e.g. Caloptcry.v. 



Figure 2. A Calopterygine wing-e.g. Diphlebia. which shows Ag- 

 rionine affinities in MA as well as in its antenodal characters. 



Figure 3. Representatives of such genera of de Selys' legion Platyc- 

 nemis as Platyscelus (P/atycnanis), Idiocucinis, Tatocnemis. Cocliccia 

 (Trichocncinis), Copera (Psilocnemis') , Allocnemls. and Chlorocucmis, 

 (but not Calicnemis or I.eptocncinis [Hemicnemis] in the former of 

 which A and Cu2 are not in the same line but are as in Figure 5. and 

 in the latter of which MA and its parts are as in Figure 5); and in the 



