NO. 6 GRASSHOPPER ABDOMEN SNODGRASS 27 



of 266 (figs. 12, 25 A), the fibers converging dorsally and anteriorly 

 to their insertion on the lateral lobe of the epiphallus (fig. 25 A, D) ; 

 its contraction probably elevates the distal part of the phallic apparatus. 



268, 26g. Internal lateral muscles (fig. 12). — Two large oblique 

 muscles on each side in the position of the second internal lateral of 

 the pregenital segments. The first is inserted ventrally on the lateral 

 margin of the ninth sternum ; the second is inserted by a narrowed 

 stalk at the edge of the ninth sternum between the basal and distal 

 plates of the latter. 



2/0. External lateral muscle (fig. 12). — This muscle clearly cor- 

 responds with the first external lateral of the pregenital segments. 

 It arises on the anterior lateral area of the ninth tergum and is in- 

 serted on the outer face of the apodeme of the ninth sternum. 



In the ninth segment of the female there are the following 10 paired 

 muscles or sets of muscles, including the segmental muscles and the 

 muscles of the ovipositor. 



260. Internal dorsal muscles (fig. 14). — A transverse series of 

 five small bands of longitudinal fibers on each side extending from the 

 anterior margin of the ninth tergum to the anterior margin of the 

 tenth tergum. 



261. Not represented in the female. 



262. Long protractor of the otnpositor. — Origin laterally on the 

 posterior margin of the ninth tergum (figs. 14, 17 C), extends for- 

 ward to its insertion on the anterior end of the apodeme of the ovi- 

 positor (fig. 17 C). 



26^. Retractor of the ovipositor. — Origin on the anterior margin 

 of the ninth tergum (figs. 14, 17 C) ventrad of 262, extends pos- 

 teriorly to its insertion laterally in the base of the dorsal valvula of 

 the ovipositor (fig. 17 C). 



264. Ventral dilator of the rectum. — A fan-shaped group of slender 

 fibers arising from the dorsal surface of the apodeme of the oviposi- 

 tor (fig. 17 B), spreading to their insertions on the ventrolateral line 

 of the rectum (fig. 16 A). If the ventral dilators of the rectum are 

 identical in the male and female, their origins would seem to identify 

 the apodemes of the ovipositor with the anterior apodemes of the 

 ninth sternum in the male. 



26§-2yo. — These muscles of the ninth segment present in the male 

 (fig. 12) cannot be identified with any certainty in the female, though 

 it is possible some of them are included in the following musculature 

 of the ovipositor. 



2yi. Levator of the dorsal vcdvula (fig. 17 A, B, C). — A large thick 

 muscle lying on the dorsal surface of the apodeme of the ovipositor. 



