464 



INDEX 



Receptor cell, 6 



Receptor-effector system, of hydra, 218, 



222, 224 

 Reconstitution, 



of athecatc hydroids, 304 



of Campanularia, 304-306 



of Cordyloplwra, 304 

 Redifferentiation, of cnidoblasts, 314 

 Reduced weight, 



apparatus for measurement, 257 



to measure mass of Anthopleura, 256 

 Reefs, coral, 



defined, 269 



see also Coral reefs 

 Reef-building organisms, calcification by, 



269 

 Regeneration, 



aging on, 404 



of Campamihma, 307-309, 397 



cell migration in, 416 



chemical inhibition of, 399-412 



of Conhjlnphora, 308 



criteria for, 400 



depression on, 406 



environmental factors on, 399, 405 



extrinsic factors on, 404 



factors influencing, 399 



genetic differences in, 401, 403 



histological studies of, 399, 409, 410 



hydro.xyproline changes in, 316 



inorganic ions on, 405 



interactions during, 406 



interaction of cell layers on, 419 



interstitial cells on, 415 



intrinsic factors on, 400, 401 



lipoic acid on, 399, 408, 414 



measurement of, 400 



mechanical factors on, 404 



of mesoglea, 419, 420 



Microsporidia on, 404 



mitosis during, 315, 418 



of mucous cells, 44 



nutrition on, 405, 406, 420 



osmolarity on, 405 



oxaloacetate on, 410 



pH on, 405 



of planaria, 410 



removal of gastrodermis on, 420 



reversal of lipoic acid inhibition, 409 



site of cutting on, 404, 406 



symbiosis on, 404 



temperature on, 405 



of tentacles, 416, 417 

 Regression, Campantilaria, 304, 379-383 



electron micrograph of, 383 



Regression, Campanularia, 



intracellular disorganization in, 383, 

 384 

 Retraction, of nematocyst tubule, 85 

 Rhabdoides, 189 

 Rhopaloides, 189 

 Rhapalonemes, 189 

 Rhvthmicitv, of sexual differentiation, 



363-372 ' 



of different hydra races, 368 



of H. littoralis, 363, 365 



of H. via^nipapillata, 366 

 RNA distribution, in budding hydra> 



441-448 passim 



Scleractinia, in reef building, 269 

 Sea anemone, 180 



see also Metridium, Calliactis 

 Sea water, artificial, 246 

 Secretory cell, differentiated from cnido- 



blast, 314 

 Sense hair, of nerve cell, 70 

 Septa, of desmosome, 58 

 Septate desmosomes, 62 



of Pelamatolujdra, 56 



see also Desmosome, Terminal bars 

 Serotonin, see 5-Hydroxytryptamine 

 Sertularians, growth zone of, 300 

 Sexual differentiation, 337-372 passim 



aeration on, 348, 354 



age on, 354 



amino acid metabolism, relation to, 

 361 



bicarbonate on, 354 



on budding rate, 366 



changing culture solution on, 354 



chilling on, 348 



of C. viridissima, 360 



contaminating organisms on, 366, 367 



of Cordijlophora, 358 



crowding on, 354 



depth on, 354 



factors affecting, 353 



feedback factors affecting, 337-362, 

 passim 



genotype on, 354, 368 



gradients, affected by, 359 



Heisenberg's principle, relation of, 344 



and Krebs cycle, 361 



a mechanism for, postulated, 361 



nutrition on, 354 



occurrence in nature, 371 



pCO., control by, 342, 343, 347-349,. 

 354 



