go ECONOMIC ZOOLOGY AND ENTOMOLOGY 



By removing all of the dorsal body-wall except the part 

 surrounding the madreporic plate and the anus, the internal 



eye spot 



muscles o, 



cardiac stomach 

 intestinal caecum 



'muscles of the pylorit caeca 



FIG. 31. Dissection of a starfish, Asterias sp. male. 



organs are exposed. The large alimentary canal is divided 

 into several regions. The short esophagus leads from the 



