42 Psyche [April-June 



times called the uncus or tegumen, and a ventral prolongation 

 possibly homologous with the lower portion of the structure 

 labeled "ep" in Fig. 16 is sometimes called the scaphium in 

 Lepidoptera. 



In the Dipteron shown in Fig. 10, the dorsal plate "ep" is 

 probably the tergite of the ninth segment alone; but I am not sure 

 of this point. The elongate slender processes "sg" resemble 

 cerci; but I am more inclined to regard them as lateral processes 

 of the ninth tergite possibly homologous with the lateral lobes 

 "sg" of Fig. 21, and I have therefore referred to them as the 

 surgonopods in the following discussion. They are possibly 

 homologous with the structures referred to as "gonopods" in 

 such Neuroptera as Ithone (See Crampton, 1918a Fig. 14); but 

 these structures in both cases are probably homologous with the 

 parts termed surgonopods in the insects described in the present 

 paper. I would likewise use this opportunity of calling attention 

 to the fact that the lateral plates called paraprocts in the paper 

 referred to above as dealing with the Neuroptera, etc. (Crampton, 

 1918a) are not the true paraprocts "pr" of Figs. 11, 12, etc., 

 but are homologous with the lateral plates of the ninth segment 

 called gonopleurites in the present paper ("pp" of Figs. 20, etc.). 

 The basal segment of the gonopods labeled "g" in Fig. 10 has 

 probably united with the pleural region to form the apparent 

 basal segment "g," while the distal segment "h" is distinct and 

 well developed. The terminal portions of both gonopods "h" 

 and surgonopods "sg" bear short spine-like structures which 

 are apparently of use in enabling the forceps-like structures to 

 hold more securely. The sternite of the ninth abdominal segment 

 "ha," forms a hypandrium or plate below the genitalia of the 

 male, as in the Neuroptera and sawflies. 



The principal points brought out in the preceding discussion 

 may be briefly summarized as follows. The epiproct, or plate 

 above the anal opening ("ep" of Figs. 11, 17, etc.) is usually formed 

 by the tenth tergite, or the tenth united with the ninth tergite 

 (or a portion of it). In some cases the region above the anal 

 opening may grow downward on either side, or unite with other 

 regions to form a proctiger ("ep" of Fig. 16?) through which the 

 alimentary tract opens. Lateral prolongations of the ninth 

 tergite form the surgonopods "sg," or dorsal structures frequently 

 employed as upper claspers in mating. The pleural plates of the 



