[ 9 6 



MANUAL OF ZOOLOGY 



SECT. 



stomatogastric or visceral system, distributed to the anterior 

 part of the alimentary canal. 



The tentacles and palpi, as well as the cirri, are probably 



n- 



FIG. 105. Nereis. Anterior portion of nervous system, comprising the brain, the 

 cesophageal connectives, and the anterior part of the ventral nerve-cord. (After 

 Quatrefages.) 



organs of the sense of touch. The only other sense-organs 

 are the four eyes, situated on the prostomium. The eye 

 consists of a darkly pigmented cup, the retina, \vith a small 



