Popular science monthly . facedownward at tlic brookside, andwith shaded eyes watches the busylife that there has its being, will see, inmany places, little masses of smallstones or bundles of small sticks, movingon the bottom of ciuiet pools as thoughthey were alive. When out of the watiTthey seem to be only groups of stones orclusters of sticks, motionless and they are the homes of living lar\ putting them in water or by pullingthem apart, a whitish habitant isdiscovered—a larva which is a daintymorsel much relished by fish. Naturehas provided it with an ingenious meansof prote
Popular science monthly . facedownward at tlic brookside, andwith shaded eyes watches the busylife that there has its being, will see, inmany places, little masses of smallstones or bundles of small sticks, movingon the bottom of ciuiet pools as thoughthey were alive. When out of the watiTthey seem to be only groups of stones orclusters of sticks, motionless and they are the homes of living lar\ putting them in water or by pullingthem apart, a whitish habitant isdiscovered—a larva which is a daintymorsel much relished by fish. Naturehas provided it with an ingenious meansof protection. The little caddis fly larvais an exemplification of the old sayingthat necessity is the mother of inven-tion, since the little animal does notalways build as his ancestors built butadapts himself to the circumstances ofa new environment and utilizes whatevermaterial may be available. In somelocalities the cases are made of stones;in others of short twigs; in still others,some of the little builders and mechanics. Little masses ofsmall stones orclusters of sticks,motionless anddead, are the homesof the caddis flylarvae much rel-ished by tiny dwell-ings actually moveabout as if alive inthe water, but showno signs of anima-tion on dry is a difficult mat-ter to induce thelarva to leave hissafe retreat bori- out the interior of a slender twig orstraw and use the hollow as a protectionagainst the enemy fish. When caddis flies are placed in smallatjuaria they extend the bcjdy out of theIront of the protecting case and carryit as they crawl. Hut jar the receptacleand the larva instantly retreats into itshouse. It is hardly possible to pull thelittle creature out of its case, exceptpossibly from the smooth straw. Itclings to its covering with peculiartenacity by means of two hooks at therear extremity of the body. So firmlyis it anchored to the sticks that violencewill not dislodge it, unless the force issufficiently great to pull the insect in the la
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Keywords: ., bookcentury1800, bookdecade1870, booksubjectscience, bookyear1872
