PROC. ENT. soc. WASH., VOL. 21, xo. 6, juxE, i gig 133 



are usually located rather close to the penis valves "pv." The 

 penis valves "pv" (Figs, i, 7, 13, 21, 26, 27, etc.) may constitute 

 the true penis, but there is some reason for considering that they 

 form a "pseudopenis" enclosing a delicate structure which repre- 

 sents the true penis. The enclosed delicate structure, however, is 

 so fragile and poorly preserved in the material available for study, 

 that I am unable to determine whether it represents the true 

 penis, or is merely the coagulated seminal fluid although from 

 its rather constant form in the insects studied, I am inclined to 

 regard it as a definite structure representing the penis of other 

 insects. 



In the lower sawflies and siricid group (Figs. 19, 28, 53, etc.) 

 and also in Xiphidria and Ceplnts (Figs. 20 and 21) which are 

 closely related to the siricids, the copulatory ossicles "gl" and the 

 sclerites "pal" are located on that side of the "genitalia" which 

 is ventral when in situ, and this very probably represents the 

 original condition of the parts. In certain other sawflies, how- 

 ever, such as Cimbex (Fig. 14), Dolerus (Fig. 40), etc., the copula- 

 tory apparatus as a whole has been turned over (revolving on its 

 long axis) so that the copulatory ossicles "gl" and the sclerites 

 "pal" which were formerly ventrally located, now come to lie 

 on the dorsal surface of the copulatory apparatus when in situ. 

 The "twisted" appearance of the membrane and muscles at the 

 base, of the "genitalia" frequently gives evidence of this revolu- 

 tion of the copulatory apparatus through 180 degrees (on its 

 long axis), but there is no sign of a "torsion" in the chitinous 

 plates themselves, since the copulatory apparatus revolves as a 

 whole, and if one were not prepared to look for such a revolution 

 of the "genitalia" by the analogous condition occurring in some 

 Diptera, etc. (in which there is a similar "inverting" of the parts), 

 it would be rather confusing in attempting to homologize the 

 parts of the "genitalia" in those insects in which such a "torsion" 

 occurs. Thus Newell, 1918, was apparently unaware that there 

 has been such a torsion of the copulatory apparatus in Dolerns, 

 and attempts to homologize parts originally or primitively dorsal 

 in sawflies (and only secondarily ventrally located in Dolenis 

 through a revolving of its copulatory apparatus through 180 

 degrees) with parts which are always ventral in Lepisma, etc. ; 

 and many of the interpretations of the parts, especially in Neurop- 

 tera, Mecoptera, sawflies, etc., given by Newell, 1918, are not at 

 all in accord with the conclusions I have reached from an ex- 

 amination of a rather extensive series of these insects, and the 

 lower forms. 



In attempting to intepret the parts of the "genitalia" of a saw- 



