312 HALF HOURS WITH IXSECTS. [Packakd. 



spins a thin, silken, whitish cocoon. Other species take up 

 their abode in galls made by two-winged gall gnats, and are 

 hence called guest or "inquiline" saw-flies. These galls are 

 sometimes inhabited also by a caterpillar, so that we have a 

 saw-fly caterpillar, a true caterpillar, and a maggot making 

 use of the same kind of gall. They do not, however, crowd 

 into the same domicile at once. In this case at any rate 

 nature does not set the laws of hygiene at defiance, and 

 crowd two or three fiimilies in a single room. The necessi- 

 ties of modern civilization, or an outgrowth from it in our 

 cities, crowd several families in a single room. Is not a 

 human life of as much accouut as a caterpillar's? 



The saw-flies with their exceptional gall-making habits 

 anticipate in nature the true gall flies, those singular beings 

 Fig. 244. ^^ whom a gall is their world, and 



the gall of bitterness a perennial foun- 

 tain of nectar. To these little white 

 maggots, the young gall flies, the poor 

 scribbler who is obliged like Douglas 

 Jerrold to feed his family "out of an 

 inkstand," owes his all. Quite uncon- 

 Basket Worm. scious of the responsibility resting 



upon him, our maggot, truly an "unconscious automaton," 

 by its simple presence in the leaf or stem, and with no more 

 intention to be an agent in bringing about a desired result 

 than though it were a grain of sand, lies passively in its cell, 

 while the growth-force of the plant erects a house over and 

 around this foreign body. No more intellectual act is needed 

 on the part of the guest than in its unconscious host, the 

 plant. The case of the gall maggot is an excellent example 

 of "unconscious automatism," while I imagine the reader 

 will agree with me that the case of the white ant, or the true 

 ants, as well as many bees and Avasps, is of an entirely dif- 

 ferent order and oarries us into a sphere where tlie sensibili- 

 ties, the will, and the intellect exert at least some force. 



24 



