Marvels of insect life ; a popular account of structure and habit . ly revealed the previously existing chrysalis, which in turn perishedto set free the winged butterfly. This was not a correct view, though later investiga-tions have shown that there was a small basis of fact in the existence of \\-hat areknown as imaginal discs. What we know as metamorphoses are reallx onlx- acontinuation of the changesthat have brought aboutthe evolution of the cater-pillar from the embr\o in the egg. To have enabled all these changes to take place in the egg would have necessitated the produc-tion of only o
Marvels of insect life ; a popular account of structure and habit . ly revealed the previously existing chrysalis, which in turn perishedto set free the winged butterfly. This was not a correct view, though later investiga-tions have shown that there was a small basis of fact in the existence of \\-hat areknown as imaginal discs. What we know as metamorphoses are reallx onlx- acontinuation of the changesthat have brought aboutthe evolution of the cater-pillar from the embr\o in the egg. To have enabled all these changes to take place in the egg would have necessitated the produc-tion of only one or two enormous eggs insttad of hundreds, and tlic In-cct would lia\e had to grow allt r tile wingetl lorni had Wv\] reached. As it i>, tlitre is no growth after \\\v linal instar lias been six true lt\gs of the caterpillar mav Ix c o n s i d e re d permanenl structures. The\ de\(>lop ( into the feit of the long legs of the butt(i(l\-, and any injurN to lluin in the caterpillar ^tag(? pro-duces some abnormalitv in the legs of the Photo by] .\ 1,1,1 Chirk. OF A small portion of the cluster of cgRs laid by ;lie ligli: brociuic moih oi. broom and otluTplants. They are magnified thirty times, and serve to illustrate the beautiful manner inwhich the eggs of Insects are frequently sculi)tured. Latin, a mask. 98 Marvels of Insect Life, The wings also exist in the caterpillar in the shape of folded buds. The feeding of thecaterpillar results in the storing of a large quantity of formative material knownas the fat-body. In the chrysalis this is drawn upon to provide for the growth ofthe wings and other structures of the complete Insect. The chrysalis is formed,of course, before the last caterpillar skin is cast off. A little before what is generallyknown as pupation, the full-grown caterpillar ceases to eat, and the pupal structuresthen undergo rapid expansion at the expense of the fat-body. Changes take place inthe nervous system and the digestive
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Keywords: ., bookcentury1900, bookdecade1910, booksubjecta, booksubjectinsects
