HARD PARTS OF THE GRASSHOPPER. 



247 



The dorsal portion of the pronotum is prolonged back- 

 wards along the median line, and partially overlaps the 

 second division or mesothorax. The anterior portion of 

 the pronotum is crossed by three grooves or sutures, which 

 divide it into four immovably united areas. 



(i.) The first of these, which forms the anterior margin 

 of the pronotum, is known as the prothoracic jpresciUum 

 (Fig. 130, 3). 



Fig. 132. — Ventral view of 

 the thoracic region of Acridium 

 Americanum. (Drawn from 

 nature by W. K. Brooks.) 



a. Prostemum. a'. Median, 

 and a", lateral portions of me- 

 sostemum. a'". Median, and 

 a'\ lateral portion of meta- 

 stemum. a", cC\ First abdom- 

 inal sternum. a'^K Second 

 abdominal sternum. h. Me- 

 dian spine of prostemum. 



c. Prothoracic episternum. 

 c'. Mesothoracic episternum. 

 c". Metathoracic episternum. 



d. Prothoracic coxa. d'. Meso- 

 thoracic coxa. d". Metatho- 

 racic coxa, e. Prothoracic 

 trochanter, e'. Mesothoracic 



trochanter, e". Metathoracic trochanter. /. Prothoracic femur, f. 

 sotboracic femur. /' . Metathoracic femur. 



Fig. 132. 



Me- 



(ii.) The second is the prothoracic scutum (4). 



(?ii.) The third is the prothoracic scutellum (5). 



(iv.) The last is the \)vothowiC\c postscuteUum {6). 



h. The ventral portion of the prothorax is formed by a 

 slender movable sternum (Figs. 130, 7, and 132, a), 

 which connects the sides of the pronotum with each other. 

 On the median line it carries, in this species, a large hairy 

 club-shaped spine (Figs. 132, b, and 139, b). Near the 



