138 ENTOMOLOGICAL NEWS [May, '22 



Enallagmas Collected in Florida and South Carolina 

 by Jesse H. Williamson with Descriptions of 

 Two New Species (Odonata, Agrionidae). 



By E. B. WILLIAMSON, Bluffton, Indiana. 



(Continued from page nS) 



The male of concisitin runs out in Calvert's key to pictnm, 

 which species it resembles very closely, the only reliable char- 

 acter for their separation I have detected being in the distinctly 

 longer and differently shaped abdominal appendages of 

 co.ncisuin. A small color difference seems to be constant: in 

 pic tn in the second lateral thoracic black stripe is abruptly nar- 

 rowed at three-fourths or two-thirds its length to narrow line 

 for the anterior fourth or third of its length; in concisitin the 

 stripe widens almost uniformly from its most anterior end 

 to the posterior end. 



In Calvert's key to the known females of the group, 

 concisiiin has the wide black humeral stripe of his first divi- 

 sion, but due to the shortening of the mesostigmal lamina 

 (hence the specific name), the meeting of the black stripe and 

 the lower end of the mesostigmal lamina is by a point only. 

 Concisiiin would then run out to plctum, from which species 

 it is separated in the following key which is supplementary to 

 Calvert's key. 



in concisum (and pictnm) the pale colored legs of the 

 female, with the femora conspicuously dark on the dorsum, 

 are in marked contrast with the orange, and entirely unmarked, 

 legs of the male. Also it is a curious fact that in concisnin, 

 where the male abdominal appendages are conspicuously 

 longer than in its near ally, picinin. the female mesostigmal 

 laminae, which these appendages grasp, in concisiiin are much 

 shorter than in pictum, but in the single female of concisum 

 I have seen there is on either mesinfraepisternum, near its 

 upper edge, and below the lower edge of the mesostigmal 

 lamina, a distinct small round contact point which, in all likeli- 

 hood, is engaged, during mating, by the supero-internal sub- 

 apical hook of the superior appendage. 



