NO. 6 



GRASSHOPPER ABDOMEN SNODGRASS 



of the acrotergite of the first abdominal tergum, accompanied by an 

 obliteration of the conjunctiva behind the wing-bearing plate of the 

 metathorax, is clearly, therefore, a device to suppress intertergal move- 

 ment at this intersegmental junction. 



Papt 



Fig. 4. — Dorsal view of the inner surface of the skeletal plates of the meta- 

 thorax and abdomen of Dissosteira Carolina, female ; ovipositor removed ex- 

 posing the floor of the genital chamber, the gonopore (Gpr), and egg guide (eg). 



The ventral union of the abdomen with the thorax in Acrididae is 

 even more complete than is the dorsal union. The sternum of the first 

 abdominal segment (fig. 2 B, IS) forms virtually a part of the ptero- 

 thoracic plastron. Its acrosternite is either a broad lobe (fig. 4, ost), 

 or a narrow tongue (fig. 2 B, ast), but in either case it is solidly fused 



