Waed. — Nectonema. 



PLATE VI. 



Figs. 72-88. Successive transverse sections through the brain. The small ner- 

 vous nuclei are represented by simple dots, the nuclei of the large 

 cells as accurately as possible ; the cell bodies are not represented. 



Fig. 72 is the twelfth section from tiie apex of the head ; each section is represented 

 from its anterior face, and approximates 10 /x in thickness. Ehrlich's 

 haematoxylin. 2. A. X 95. 



Fig. 89. The posterior end of tlie male with anal ganglion and dorsal sac viewed 

 as a transparent object in clove oil. Only a few of the numerous Gre- 

 garinida (*) in the body cavity are represented. 2. A. X 66. 



