420 



COMPARATIVE ZOOLOGY 



The wormlike larva 17 may be called a locomotive egg. 



It has little resemblance to the parent in structure or 



habits, eating and 

 growing rapidly. 

 Then it enters the 

 pupa state, wrapping 

 itself in a cocoon, or 

 case, and remaining 

 apparently dead till 

 new organs are devel- 

 oped, when it escapes 

 a perfect winged in- 

 sect, or imago. 171 

 Wings never exist ex- 

 ternally in the larva ; 

 and some insects 



i 10.368. Milkweed butterfly: A, head of young larva; 

 B, larva; C, pupa; D, imago; E, egg (magnified), which Undergo no 



apparent metamorphosis, as lice, are wingless. The 



3 



FIG. 369. Metamorphosis of the Mosquito (Culex pipiens}'. A, boat of eggs ; B, some 

 of the eggs highly magnified ; d, with lid open for the escape of the larva, C ; 

 D, pupa; E, larva magnified, showing respiratory tube, e, anal fins, f, antennae, ; 

 F, imago; a, antennae; b, beak. 



