SUB-KINGDOM III. -^ANNULOIDA. 



37 



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

 Reproductive organs external. Ex., Fresh-water Polypes, Sca-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. 



pjg. 9.— Annuloida. n Holothuria tidudosn, one of the Sea-cucumbers ; 

 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 

 3 



