288 



PROCEEDINGS OF THE AMERICAN ACADEMY. 



VII. 



VI.':' 



Vlllj 



Fig. 1. Dorsal view of the anterior part of tlie body of Glossiphonia para- 

 sitica Say (Clepsine hollensis Whitman), showing in the right lialf of the figure the 

 nervous system ; in the left half, the lymph system (stippled). The pear-shaped 

 dark bodies shown on certain rings are dorsal sense organs, d., stump of a nerve 

 branch which innervates dorsal sense organs on all three rings of a somite. 

 nph'po., nephropore. va.t., transverse lymph vessel. Somite limits are indicated 

 by roman numerals, at the left of the figure (I. -VII.'), according to Whitman's 

 view ; at the right (I.-VIII.), according to the view of the writer. After Whit- 

 man ('92), simplified. 



