90 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 



nuscles of the fylorif caeca, 



musclei of the pyloric caeca 



eye spot -- J 



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 



