SUB-KINGDOM III. ANNULOIDA. 37 



those of the general body-cavity, the two coinciding with one another. 

 Reproductive organs external. x. t Fresh-water Polypes, Sea-firs, 

 Portuguese Man-of-War, Jelly-fishes, Sea-blubbers. 



CLASS B. ACTINOZOA Stomach opening below into the body-cavity, 

 which is divided into a number of compartments by vertical partitions or 

 "mesenteries." Reproductive organs internal. Ex., Sea-anemones, 

 Star-corals, Brain-corals, Sea-pens, Sea-shrubs, Red-coral, Venus's 

 Girdle. 



SUB-KINGDOM III. ANNULOIDA. 



Animals in which the alimentary canal (when present) is completely 

 shut off from the general cavity of the body, and in which there is 

 a peculiar system of canals, distributed through the body, usually 

 communicating with the exterior, and termed the " water- vascular " 

 system. A distinct nervous system, and sometimes a true blood-vascu- 

 lar system. The body of the adult never composed of a succession of 

 definite rings or segments, nor provided with successive pairs of append- 

 ages disposed symmetrically on the two sides of the body. Reproduc- 

 tion rarely asexual. 



Fig. 9. Annuloida. n Holothuria tubulosa, one of the Sea-cucumbers J 

 b and c Young stages of the same (after Jones). 



CLASS A. ECHINODERMATA. Integument composed of numerous 

 calcareous plates jointed together, or leathery, and having grains, spines, 

 or tubercles of calcareous matter deposited in it. Water-vascular system 



