OTHER ORDERS OF INSECTS 



131 



For lack of space we shall have to dismiss the other orders 

 with a mere mention. There are two orders that have no 

 metamorphosis: 



Thysanura or bristle-tails, and 



Collembola, or springtails. 



These hatch from the egg in the form they will retain 

 through life, and bear no signs of wing development. 



There are four orders that are small, wingless, parasites: 



Mallophaga, or bird lice. 



Anopleura, or true lice, three species of which infest man. 



Siphonaptera, or fleas. 



Strepsiptera, or stylopids, that 

 infest other insects. 



There are two orders that are minute 

 winged insects, scarcely reaching a 

 fourth of an inch in length : 



Thysanoptera, or thrips, very 

 slender insects that are common in 

 the heads of flowers, and that may 

 be found by pulling apart such flowers 

 as daisies and clover. The narrowly 

 linear, nearly veinless wings, bearing 

 long fringes of hairs, are laid flat upon 

 the back. A few of these are important garden pests. 



Corrodentia, or psocids, bark and crevice inhabiting 

 insects having two pairs of rather broad wings, that are 

 traversed by zig-zag veins, held when closed rooflike over 

 the body and not folded. The antennae are long and slender. 



Fig. 53.— The fire brat, 

 one of the Thysanura that 

 lives around furnaces and 

 kilns. 



