PLATE XXXIII. 



Figs, 1-6. Ascidia translucida, Herdman. 

 Figs. 7-9. Ascidia cylindracea, Herdman. 

 Figs. 10-12. Ascidia despecta, Herdman. 



Fie. 1. Ascidia translucida, from the right .side : natural size. 



Fig. 2. The same from the left side, showing the vascular ramifications in the test ; 



natural size. 

 Fig. 3. Part of the branchial sac of Ascidia translucida, seen from the outside, and 



showing "minute plication" ; magnified (Hartn., obj. 4). 

 Fig. 4. Part of the same branchial sac, seen from the inside ; magnified (Hartn., obj, 4). 

 Fig. 5. The tentacles and the dorsal tubercle, &c, of Ascidia translucida ; magnified 



(Hartn., obj. 4). 

 Fig. (5. Part of the dorsal lamina of the same species ; magnified (Hartn., obj. 4). 

 Fig. 7. Ascidia cylindracea, from the right side ; natural size. 

 Fig. 8. Part of the branchial sac of Ascidia cylindracea, seen from the inside; magnified 



(Hartn... obj. 4). 

 Fig. \). Part of the dorsal lamina of the same species, showing the sinuses engorged with 



blood corpuscles; magnified. 

 Fig. 10. Ascidia despecta, from the right side ; natural size. 

 Fig. 11. Part of the branchial sac of Ascidia despecta, seen from the inside ; magnified 



(Hartn., obj. 4). 

 Fig. 12. Part of the dorsal lamina of the same species ; magnified (Hartn., obj. 4). 



