PLATE XXI. 



FIG. 



1. Plumularia falcata, p. 90, of the natural size. 



2. A portion of the same magnified. 



3. The ovarian vesicle and four of the polype-cells of Plu- 



mularia falcata magnified. 



4. Plumularia pinnata, p. 95, of the natural size. 



5. A portion of the same magnified. The ovarian vesicles 



have discharged their contents. 



6. The vesicles of Plumularia pinnata, previous to the dis- 



charge of their ova. 



