MALE GONAPOPHYSES 65 



ventral side of which is produced into a naiTow bar extending 

 across the ventral side of the aperture of the genital atrium, its 

 distal extremity bifurcating. The dorsal plate of the seventh 

 segment (vii, d.) is asymmetrical. It consists of a narrow sclerite, 

 which, on the dorsal side, is similai- to the sixth dorsal plate, but 

 the left side (see fig. 25) extends down the side, and broadens out 

 into a somewhat triangular-shaped aiva; the anterior edge of this 

 is incised, and receives the seventh spiracle (vii, a.sp.) ; the ventral 

 edge is internal to the spatulate portion of the sixth ventral plate. 

 The ventral arch of the seventh sclerite has been completely with- 

 drawn into the abdomen, and consists of a pair of curved sclerites 



Vll.d 



VI K 



Fig. 25. Lateral view of the terminal segments of the abdomen of the male after 

 their removal from the fifth segment. 



vi, a.sp. and vii, a.sp. Sixth and seventh abdominal spiracles. Lettering as in 

 fig. 24. 



(fig. 26, vii, V.) somewhat rhomboidal in shape, lying dorsal to the 

 fifth ventral arch and ventral to the penis (P.) ; they form the 

 secondary forceps. Their lateral edges, which are thickened, articu- 

 late with the alar processes of the body of the penis (c.pe.), and 

 with the dorsal arch of the eighth abdominal segment (viii, d.). 

 Their inner edges are curved, and almost meet in the mid-ventral 

 line. The dorsal arch of the eighth and last abdominal segment 

 (viii, d.) forms the apex of the abdomen. It consists of a strongly 

 convex sclerite, deeply incised on the ventral side ; in this incision 

 the vertical slit-like anus (fig. 2o, an.) lies. The ventral portion of the 

 segment is completed by a pair of convex sclerites (fig. 26, viii, v.) 



