152 ARTHROPODS: INSECTS. 



for her eggs ; but not together, for while one is pushed 

 forward, tire other is withdrawn. When the hole is 

 cut deep enough, the egg is deposited within. Saw- 

 flies are sluggish, and fly only on the warmest days. 

 The larvae are found together in large numbers on the 

 leaves of the birch and alder. When disturbed, they 

 take very curious attitudes, appearing to stand upon 

 the head, curling into an S, or coiling with the head 

 in the center looking somewhat like a snail-shell. 



Butterflies and Moths, or Lepidoptera. 



The word Lepidopter means scaly-winged, and is 

 given to these Insects because their wings are covered 

 on both sides with minute scales. These are removed 

 by the slightest touch, and to the naked eye look like 

 a mealy powder ; but when seen under a microscope, 

 they are found to be little scales attached to the skin 

 by a short stem. The tongue is long, and adapted for 

 suction ; «'hen not in use it is rolled up like a watch 

 spring beneath the head, and partly concealed on each 

 side by a little feeler. They have six legs, the first 

 pair being short, and, in some cases, folded under 

 the breast : the feet end in a pair of claA\s. The 

 young of Butterflies and Moths are called caterpillars, 

 and these have from ten to si.xteen legs. Six of the 

 legs correspond to those of the Butterfly. The rest are 

 unjointed projections of the abdomen, and are called 

 prolegs or proplegs. Most caterpillars feed upon the 

 lea\es of plants. Some eat buds, blossoms, seeds, and 

 roots, and others eat the solid wood. Some eat wool- 

 ens, others furs, others meat, lard, wax, and flour. 

 Some kinds herd together in great numbers, and build 



