GROWTH AND METAMORPHOSIS OF INSECTS. 35 



places its egg in the centre of a ball of dung, which it rolls 

 away to a secure place; the flesh-fly oviposits on fresh or 



b c d e f g h i k I 



a 



m n o p q r s 



FIG. 30. Eggs of different insects, a, Tortrix; 6, Liparis; c, a noctuid, Trachea ; 

 d, usual shape of those of bark-borer, etc.; e, Melolontha; /, Chironomus; g, 

 Lyda; h, Musca; i, honey-bee; fc, Rhodites rosae; /, Chrysopa; m, Drosophila; 

 n, Pentatoma; o, Nepa; p, Pieris crataegi; q, bed-bug; r, louse, fastened to a 

 hair; s, Hypoderma actseon, bot-fly. From Judeich and Nitsche. 



putrid meat, and moths and butterflies lay their eggs on 

 the leaves or stems of the food-plant, where the caterpillar, 

 upon its exit from the egg, shall readily find an ample 

 supply of food. 



No collection of insects is complete without specimens of 

 the eggs neatly gummed on a card and pinned next to the 

 insect. 



Growth of the Insect within the Egg. The germ or 



FIG. 31. Section of Sphinx 

 embryo, the germ im- 

 mersed in the yolk, s, 

 serous membrane; am, 

 an in ion; h, outer, m, in- 

 ner, germ-layer. 



FIG. 32. Embryo of Sphinx much more advanced. 

 h, heart; y, ganglion; i, intestine; m, rudimen- 

 tary muscular bands running to the heart; A, 

 stigma and beginning of a trachea it); d, a 

 gland. This and Figs. 33 and 34 after Kowalevsky 



young insect before hatching is called the embryo, and the 

 study of the growth or development of the embryo is called 

 Embryology. 



