180P0DA, 



289 



Fig. 257. 



Fig. 355.— Section of the embryo pill-bug. tf, inteetine; I, epithelium form- 

 ing the walls of the two lobes of the liver ; g, transverse section of the nervous cord ; 

 h, walls of the body.— After Bobretzky. 



Fia; 256.— Section of more advanced emhryo pill-bu?;. A, heart; 7iW, hypnder- 

 mal layer or body-walla ; m, mu>-cular wall of the intestine : e, epithelial lining of the 

 inteetine ; p^ dividing cell-wall betwoen the henrt and inteetine ; I, two lobes of the 

 liver ; g, gan^rlion. the clear space being filled with the fine granular substance of the 

 ganglion.- After Bobretzky. 



Piar. 2S!7.—Bopyru8. A, ventral, B, dorsal side of the female; C, lateral and Z), 

 dorsal view ot the male ; c^, head and first thoracic segment ; c^^ antennse— all en- 

 larered. — Packard, del. 



