A Cirriped Crustacean. 103 



the mouth to the short, straight oesophagus. The latter opens 

 suddenly into a large stomach. Numerous dark hepatic 

 glands will be seen on the walls of the stomach. The 

 intestine is a straight tube of uniform size, extending from 

 the stomach to the anus. 1 



Make a drawing of the alimentary tract as seen from the 

 side. 



Excretory System. Glandular bodies, possibly excre- 

 tory in function, have been described as opening from the 

 second maxillae. The cement glands of the first antennae 

 may also belong to the category of excretory organs. 



A closed Circulatory System is not present in the Cirri- 

 pedia. Near the base of the oral cone, on either side of the 

 animal, five elongated filaments are to be noted. These 

 organs are probably respiratory in function. 



The Muscular System is developed chiefly for the 

 movement of the divisions of the shell, the waving of the 

 appendages, and the retraction of the soft parts. The young 

 (Nauplii) are active swimmers. 



The arrangement of the muscles that move the mouth 

 parts can often be seen through the transparent integument 

 of the oral cone. 







The Nervous System. Remove the stomach and 

 intestine from the opening already made in the side of the 

 animal. The nervous system occupies, as a chain of ganglia, 

 a median ventral position. Anteriorly it surrounds the 

 oesophagus (cesophageal ring or collar}, and unites with the 



1 On either side of the oesophageal end of the stomach is a whitish 

 glandular organ, which may be called the " pancreas." 



