202 THE EMBRYOLOGY OF THE HONEY BEE 



Mint 



Cbl 



DLMcL... J 



TraTr 



OMcl--' 



TraConr'' 



FIG. 81. Transverse section through the third trunk segment of an 

 embryo,- Stage XII, x 387. 



Mint) it covers the lateral face of the yolk and has now reached 

 the ventral surface. The rudiment of the enteric muscles has 

 followed this ventrad growth, but only imperfectly so. A short 

 distance back from the ventral edge of the rudiment of the mesen- 

 teron are four scattered muscle nuclei, while dorsad of this the 

 forming muscle cells form a continuous layer which is joined to 

 the cardioblasts. The appearance of the section suggests that the 

 cells of the rudiment of the enteric muscles had been forcibly 

 dragged apart by the rapidly growing epithelium of the mid- 

 intestine. 



A section through an embryo of Stage XIII-XIV (Fig. 82) 

 shows the process of differentiation nearly completed. The hypo- 

 dermis extends on each side up to the dorsal mid-line. The 



