MORE ABOUT INSECTS 73 



easy life by appropriating for itself food collected and intended 

 for the ants' young. Related to this is a very large one in the 

 Indian region which lives in the nests of the green tree-driver 

 ant eating their young. 



The caterpillars of several other kinds, among them one of 

 ours, feed wholly on aphids or scale insects, and a few ad- 

 ditional eat these in their later stages. Some eat other in- 

 sects. Other lycaenid caterpillars feed on bark and lichens, 

 or bore into fruits or seeds. 



The caterpillars of most of these pretty little butterflies are 

 cannibals, and especially prefer to eat their friends just as they 

 are changing to the pupa stage. 



Moths are much more varied in their habits than are the 

 butterflies, just as they are also far more numerous. A num- 

 ber of them as caterpillars feed in ant nests on young ants, or 

 on scale or other insects, or on the excretions of fulgorids. 

 A few are parasities in other caterpillars like the grubs of 

 tachinid flies. Many eat dry animal matter of all kinds, 

 including horn. One lives in the water in the leaves of our 

 common pitcher-plant eating the insects which the plant has 

 caught. In the American tropics one eats only a certain hchen 

 which is never found except upon the rough and brittle hair of 

 living sloths. Most moths, of course, like nearly all the butter- 

 flies, are vegetarians, mostly leaf feeders, sometimes borers. 



Is there any better food than lobster or crab meat? If there 

 is, then one whole group of insects shows poor judgment, 

 for they eat nothing else, except that for them minute crus- 

 taceans replace the crabs and lobsters. These insects, related 

 to the common water striders of our ponds and streams, live 

 upon the surface of the ocean, often far from land, picking 

 these dainty morsels from the water. These are the only truly 

 marine insects, though a spider, some centipedes, and a few 

 spring-tails and carabid beetles live under stones between tide 

 marks, and the spring-tails on the surface of tide pools, and 

 the various beach-flies live in the rotting sea-weed cast up by 

 the waves. 



