62 



ZOOLOGY 



SECT. 



FIG. 45. Aulactinium actinastrum. c. calymma ; km. central capsule ; n. nucleus ; op 

 operculum ; ph. phaeodium. (From Lang's Comparative Anatomy, after Haeckel.) 



cent, caps 



FIG. 46. Actinomma asteracanthion. A, the shell with portions of the two outer 

 spheres broken away ; B, section showing the relations of the skeleton to the animal ; 

 cent. caps, central capsule ; ex. caps. p>: extra-capsular pi-otoplasm ; nu. nucleus ; sk. 1, outer,.- 

 sk. 2, middle, sk. 3, inner sphere of skeleton. (From Biitschli's Protozoa, after Haeckel and 

 Hertwig.) 



