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THE POPULAR SCIENCE MONTHLY. 



maroon, with some parts the head, for example remaining 

 darker. 



Larvae are to be found, we might say, everywhere and in every- 

 thing on the leaves and roots and in the interior of plants, nnder 

 the ground, in putrefying matter, in the tissues of living animals, 

 in cloths, and in water. Wherever they are found, these larva? 

 are busy, before everything else, in alleviating the hunger of the 

 moment. They devour, and they gorge themselves, without taking 



any care to protect their exist- 



ence asrainst 



aggressors 



from 



without. But a more provident 

 minority construct shelters for 

 themselves little movable houses 

 which the animal carries with it- 

 self, and within which it with- 



Fig. 3. Larva with Articulated Legs and Fig. 4. Cases of Phrtganides. 



with Membranous Legs. 



draws in case of danger, like a turtle in its shell. The larva fixes 

 itself to this refuge by means of its membranous legs, and moves 

 without by its articulated legs. The materials necessary for the 

 construction of the nest are gathered up in the element in which 

 the animal lives. They are twigs, grains of sand, fragments of 

 shells, collected in water by the Phryganeidce, shreds taken from 

 our cloths by the Tineidce, ; earthy substances by the Chythra ; 

 and all are glued together by the secretions of the insect. 



Whether in the open air or in water, or in the bottoms of un- 

 derground chambers, larvse, at a certain period of their evolu- 

 tion, undergo another change, and are transformed into nymphse. 

 Among the insects of incomplete metamorphosis, the nympha is 

 but little different from the larva, and molts and is fed in the 



