60 



ZOOLOGY 



SKCT 



I' ; > 



* ? 



*% 



FIG. 42. Aulactinium actinastrum. c. calymna ; km. central capsule ; n. nucleus ; op- 

 opsrculum ; p/t. phteodium. (From Lang's Comparative Anatomy, after Haeckel.) 



cent, caps 



FIG. 43. 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 : 

 c, nt. caps, central capsule ; ex. caps. pr. i-xtm-cap-mlar rirotnplasm : nu. nucleus ; sk. 1, outer, 

 sk. -2, middle, sk. 3, inner sphere of skeleton. (From Blitschli's Prntu:oa, after Haeckel and 

 Hertwig.) 



