144 ENTOMOLOGICAL NEWS. [May, '06 



A A. The two jaws of the pincers by which the male grasps the female, 

 formed by the two superior appendages, acting forceps-like, 

 or by the inferior appendages, acting in a similar manner. 

 In the case of certain species, judging from the form of the 

 appendages, superior appendages and inferior appendages 

 each act as a pair of forceps, so the female is doubly secured. 

 Also it must be noted that the two superiors acting together 

 may form one jaw of a pair of pincers, the other jaw of which 

 is formed by the two inferiors. In couple the superior append- 

 ages of the male rest behind, and the inferior appendages in 

 front, of the hind margin of the pronotum of the female. SUB- 

 ORDER ZYOOPTERA. 



B. Superior appendages of the male forming two jaws, in couple 

 grasping the most anterior portion of the mesepisternum and 

 the mesostigmal laminae of the female. 



C. Inferior appendages of the male in couple extended over the dor- 

 sum of the pronotum of the female, scarcely or not touching it, 

 and with their apices resting against the rear of the head. When 

 the abdomen of the male was disturbed the inferior append- 

 ages in some cases did not touch the head of the female, in 

 other cases the tips of these appendages were extended to the 

 top of the female's head. Undisturbed they rested against the 

 rear of the occiput, performing no work of grasping whatever. 

 All female Zygoptera observed when in couple keep the pro- 

 thorax drawn tightly against the mesothorax. Lestes. Posi- 

 tive observations in the case of L.forcipatus and L. unguiiii- 



latus. 

 CC. Inferior appendages of the male resting on the anterior side of 



the hind lobe of the prothorax of the female. Het&rina. 

 BB. Inferior appendages forming two jaws which grasp the anterior 

 surface of the hind lobe of the pronotum of the female, the 

 superior appendages resting in cups formed by depressions in 

 the mesostigmal laminae and the rear surface of the hind lobe 

 of the pronotum and, depending on their form, grasping the 

 mesostigmal laminae or rtbt. The female by drawing the hind 

 lobe of the pronotum closely against the mesostigmal lamiiur 

 prevents the escape of the male. 



D. Dorsum of apex of segment 10 of male modified to form a brace 

 against the middorsal carina or its fork or the cavity in the 

 fork. Anoinalagrion, Ischnura, Enallagina. 



DD. Dorsum of apex of segment 10 of male with a viscid pruinose 

 tubercle on either side which attaches itself to the mesepister- 

 num of the female on either side of the fork of the middorsal 

 carina, the tubercle which corresponds to the inferior append- 

 age of Anisoptera engaging the cavity in the fork between the 

 mesostigmal lamina:. Argia (putrida and apica/is). 



