PLATE XX. 



PuGET Sound Ascidians. 



PAGE. 



Fig. 4. Cynthia macrosiphonus Ritter, xi 597 



Fig. 19. Cynthia SUperba Ritter. Dorsal languets, pri- 

 mary and secondary 590 



Fig. 27. Styela Stimpsoni Ritter, Dorsal lamina 602 



Fig. 28. Gonads of same species, X 2 603 



Figs. 29 and 30. Distoma molle Ritter, the first in con- 

 tracted state, the second in extended, x 12 605 



Fig. 31. Distoma lobata Ritter, general character of 

 colony XI 606 



Figs. 32 and t,^. Same species, first in contracted state, 

 second extended, x 27 606 



(616) 



