394 BIOLOGY 



coagulate. To change into a curd-like mass, 22. 



coccus. A spherical bacterium. 



cocoon. The t >ationary stage in the life of a butterfly, 72; the egg case 



of an earthworm, 165. 

 Coelenterata (Gr. kottos = hollow + enteron = intestine) . Animals with 



pnly a single cavity and no body cavity, including Hydra and its allies, 



377. 

 coeliac axis. The arterial trunk from the dorsal aorta, supplying the 



viscera, 190. 



coelom (Gr. koilos = hollow). Same as body cavity, 157. 

 Coelomata (Gr. koilos = hollow) . Animals with a body cavity including 



all animals above Ccelenterata. 



coelomic fluid. The fluid filling the body cavity, 158, 160. 

 coenocyte (Gr. koinos = common + cytos a cell). A protoplasmic 



mass containing several nuclei, but without division into cells; same as 



syncytium. 

 cold-blooded. A term applied to animals whose blood is of essentially the 



same temperature as the surrounding medium, 

 colloidal. A term applied to substances which will not dialyze through 



membranes, 307. 

 colony. A group of connected individuals, usually arising from one by 



asexual budding, 73, 92. 

 columella. A rod connecting the tympanic membrane with the inner ear 



in the fiog, 197. 

 commensalism (Lat. cum = together + mensa = table). An association 



of two organisms in which neither is benefited nor injured, 230. 

 commissures (Lat. committere = to join). Nerve cords connecting ganglia, 



162. 



communal. Living in communities. 



compound pistil. A pistil made of several fused carpels, 120. 

 conductility. The power possessed by protoplasm of transferring impulses 



from one end to the other, 43. 

 condyies. The smooth protuberances by which the skull is attached to 



the first vertebra, 181. 



conformity to type. The appearance of like individuals in successive gen- 

 erations, 328. 

 congenital characters (Lat. con = with + genitus = born). Characters 



that are fixed in the germ plasm, 327, 334. 

 conidia (Gr conis = dust). Spores produced by constriction on the ends 



of threads rather than in a sporangium, 98. 

 conjugation (Lat. com = together + jugare = to join). The union of 



two similar cells in reproduction, 65, 94, 247, 262. 



