INSECTS INFESTING THE S)VEET POTATO. 



317 



ally held over the back, and the excreineiit.s o( tlie larva are 

 sometimes collected upon then]. 



Tlie larva of the two-striped tortoise beetle (Fig. 312, 3,) is of 

 a dirty, or yellowish white color. It differs from the other three 

 mentioned below by not collecting its excrements upon its 

 anal spines. 



Fig. 317. Fig. 318. 



Fig. ol7. — Larva of Golden Tortoise Beetle ; (/, several lar- 

 vae on a leaf; b, a larva, enlarged — color, dark l)rown. 



Fig. 318. — Larva and pupa of Mottled Tortoise Beetle; a, 

 the larva, enlarged— color, green ; b, the pupa, enlarged — color, 

 green. 



The larva of the golden tortoise beetle (Fig. .'JIT) is of a dark 

 brown color, with a pale shade upon the back. 



That of the mottled tortoise beetle (Fig. 318r/) is of a green- 

 ish color, while the larva of the black-legged tortoise beetle 

 (Fig. 319, a and b,) is of a pale straw color, marked witli dusky 

 spots, the spines tipped with black. 



Fig. 319. 







Fig. 320. 



Fig. 319.— Larva of Black-legged Tortoise Beetle; b, the 

 larva, enlarged— color, yellow; a, two larvae on a leaf. 



Fig. 320.— Pupa of Black-legged Tortoise Beetle, enlarged- 

 color, brown. 



