1920] Crampton — Genitalia of Male Hymenoptera and Other Insects 39 



extremely elongate in some Bittacus-\\ke Mecoptera, and doubt- 

 less serve as clasping organs in mating. The basal segment "g" 

 of the gonopods is very large in the Mecopteron shown in Fig. 

 21, while the terminal segment "h" is greatly reduced. The 

 penis valves "pv," however, are quite large, are partially united, 

 and bear a coiled penisfilum "b." The structure labeled "ep" 

 probably represents the tenth tergite with which the paraprocts 

 bearing the cerci "ca" have united. The structures labeled "ca" 

 may not represent the cerci ; but they occupy the position charac- 

 teristic of these organs, and have been provisionally interpreted as 

 the cerci in the present paper. 



In the Strepsipteron shown in Fig. 18, the structure labeled "ep" 

 is a "proctiger," since the anus opens at its posterior end. It is 

 probably formed largely by the tenth tergite, although a portion 

 of the ninth tergite may also be involved in its composition. The 

 structure labeled "g" may represent the hypandrium or plate 

 below the genitalia of the male (i. e. the ninth sternite) but I am 

 inclined to think that the basal segment of the gonopods also 

 enters into the composition of this structure, while the small hooks 

 labeled "h" might possibly represent the terminal segments of 

 the gonopods. The structure labeled "pv" is the ledeagus or 

 phallus, and in some Strepsiptera an intromittent organ is pro- 

 truded from the sedeagus at the time of mating. 



The sternite of the ninth segment labeled "ha" in the Neurop- 

 teron shown in Fig. 20 is well developed and is demarked from the 

 pleural region of the segment "pp." The ninth tergite is par- 

 tially produced on either side to form a pair of lobe-like structures 

 "sg," comparable to the copulatory lobes "sg" of the Mecopteron 

 shown in Fig. 21. The structure labeled "ep" in Fig. 20 probably 

 represents the tenth tergite, or the fusion product of the tenth 

 tergite and the paraprocts (or plates on either side of the anus). 

 I formerly interpreted the structures labeled "s" in Fig. 20, as 

 the penis valves (i. e. "pv" of other insects, Figs. 17, 21, etc.); 

 but there are some grovmds for considering the structures "s" 

 of Fig. 20, as the remains of the gonopods labeled "s" (which are 

 composed of the segments "g" and "h" in other insects), or a 

 portion of it, in the other figures, and I have provisionally adopted 

 the latter interpretation in the present paper. 



In the psyllid shown in Fig. 14, the tergal sclerites labeled 6 



