6 BUIXETIN TSO, U. S. DEPAETMENT OF AGKICULTUEE. 



brown. It may be quite light, approaching a yellow, or it may be 

 dark, approaching the red observed in the flesh of the ox. Stomachs 

 of the lighter shades especially are translucent. 



The rather thick walls of the stomach (fig. 2) consist of an inner 

 epithelial and an outer muscular portion. Between these is the 



LMcl 



Epih 



Pmb. 



Fig. 2.— Miorosoopic anatomy of alimentary canal of worker bee: A , cross section of stomach showing 

 peritrophio membranes (Pmb); B, wall of stomach, more highly magnified, showing epitheUal layer 

 {Epth), basement membrane (.BM), and muscular portion; C, section bf Malpighian tubule showing 

 epithelium (,Epth) and basement membrane (,BM); D, orosssectiou of small intestine. This portion of 

 the canal, the rectum, and the oesophagus have a heavily chitinized intima. (Snodgrass.) 



basement membrane. Both surfaces of the epithelial layer are 

 irregular. This consists of epitheljal cells {Efih) varying in size and ^ 

 outline. Closely associated with the outer surface of the epithelial 

 layer is the basement membrane (BM). In connection with its 

 inner surface is the more or less indefinite intima (Int) which possibly 



