METAMORPHOSIS OF PLATYGASTER. 



163 



The second larval stage (Fig. 195 ; ce, oesophagus ; ng, supra- 

 ojsophageal ganglion ; n, nervous cord ; ga, and g, genital organs ; 

 ms, band of muscles) is attained by means of a moult, as usual 

 in the metamorphoses of insects. With the change of skin the 

 larva entirely changes its form. So-called hypodermic cells are 

 developed. The singular tail is dropped, the segments of the 

 body disappear, and the body grows oval, while within begins 



104. First Larva of Platygaster. 195. Second Larva of Platygaster. 



a series of remarkable changes, like the ordinary development 

 of the embryo of most other insects within the egg. The cells 

 of the hypodermis multiply greatly, and lie one above the other 

 in numerous layers. They give rise to a special primitive organ 

 closely resembling the ''primitive band" of all insect embryos. 

 The alimentary canal is made anew, and the nervous and vascu- 



