PROC. ENT. SOC. WASH., VOL. 21, X(). 6, JUNE, 1919 loo 



(Figs. 29, and 58, "s"). If one compares the unsegmented styli 

 of the ephemerid shown in Fig. 29, "s" with the unsegmented 

 forceps of the sawfly shown in Fig. 8, "eg," there is apparent a 

 strong resemblance between the two, and the basal ring "gg" 

 of the sawfly (Fig. 8) resembles the sternite labeled "ha" in the 

 ephemerid (Fig. 29) quite markedly. This interpretation of 

 the nature of the forceps has much to recommend it. On the 

 other hand, there is a possibility that the so-called parameres 1 

 of certain lower insects (Figs. 30, 34, etc., "pm") may be the 

 forerunners of the genital forceps. 



Tracing the ontogenetic development of the parts from the 

 immature to the adult stages is one method of determining the 

 correct interpretation of the parts; but unfortunately this has 

 not been done in the case of the Hymenoptera. Klapalek, 1903, 

 however, states that the gonopods of adult Trichoptera (Fig. 52, 

 "gb" and "eg") correspond to the hindermost abdominal legs or 

 "postpedes" of the larvae (Fig. 43, "pp"), and if this be true, 

 we have a basis for determining the homologies of the forceps 

 of the Hymenoptera (Fig. 27, "gb" and "eg"), since these struc- 

 tures are homologous with the gonopods of the Mecoptera and 

 Trichoptera (Figs. 35 and 52, "gb" and "eg"), and must there- 

 fore also correspond to the postpedes of the larvae (Fig. 43, "pp"). 

 These postpedes or "anal prolegs" do not represent styli (ap- 

 pendages of the basal segment of the leg in Apterygota) but are 

 now considered to represent true abdominal legs by most recent 

 embryologists, so that if the forceps represent "anal prolegs" or 

 postpedes, they can hardly he homologized with the styli of 

 ephemerids (Figs. 29 and 58, "s"). If the genital forceps are 



1 Wheeler, 1910, in his book on ants, designates the entire copulatory 

 apparatus of the male, as the"parameres." Escherich, 1905, following other 

 students of the Apterygota, and Burr, with all modern dermapterists, have 

 used the designation "parameres" to denote the structures labeled "pm" 

 in Figs. 30, 34, etc., and there seems to be no valid reason for attempting to 

 change this widespread and generally accepted usage of the term among the 

 workers on the Apterygota and Dermaptera, especially since the application 

 of the term "parameres" to the entire copulatory apparatus of the male, 

 has been employed by only one or two students of the ants. I suggested 

 using the term phallus for the entire copulatory apparatus, as is done in 

 lower insects; but since there might be some objection to this usage of a term 

 which is made a synonym of the term penis in Smith's "Glossary," I have em- 

 ployed the designations genitalia, genital apparatus, or copulatory apparatus 

 for the parts of the male alone, in the present paper, since we already have 

 the designations ovipositor, sting, etc., for the "genitalia" of the female. 

 The designation "copulatoria" has also been suggested for the entire copula- 

 tory apparatus of the male. 



