ITI.] METAMORPHOSES OF INSECTS. 47 



moment qu'a lieu la formation des protozonites ou 

 segments primordiaux du corps de 1'embryon. Le 

 rudiment ventral s'epaissit suivant six zones disposees 

 transversalement entre le capuchon anal et le capu- 

 chon cephalique." 



Among Centipedes the development of Julus has 

 been described by Newport. 1 The first period, from 

 the deposition of the egg to the gradual bursting of 

 the shell, and exposure of the embryo within it, 

 which, however, remains for some time longer in 

 connection with the shell, lasts for twenty-five days. 



FIG. 33. Embryo of Julus (after Newport). 



The segments of the body, originally six in number, 

 make their appearance on the twentieth day after 

 the deposition of the egg, at which time there 

 were no traces of legs. The larva, when it leaves 

 the egg, is a soft, white, legless grub (Fig. 33), con- 

 sisting of a head and seven segments, the head being 

 somewhat firmer in texture than the rest of the body. 

 It exhibits rudimentary antennae, but the legs are 

 still only represented by very slight papilliform pro- 



1 Philosophical Transactions, 1841. 



