INDEX OF SUBJECTS 



Cell-division, movements in the cyto- 

 plasm during, 267 ff. 



resistance and susceptibility in, 

 272 



surface-tension in, 270 ff. 

 Cell-lineage, 241, 292 

 Cell-membrane, 70-74 

 Cells, fixation of, 65-67 



physical properties of, 42 

 Cellular oxidation, 349 

 Centres of first cleavage spindle, origin 



of, 182 

 Centrifuged eggs, 306 

 Centriole, 69, 162, 166 

 Centrosomes in fertilization, 182, 183 

 Centrosphere, 69, 162 



in cell-division, 255 

 Cerehratulus, egg of, 93 

 Chaetopterus, egg of, 64, 97, 117, 153, 

 177, 191, 223, 270, 297, 299, 



303, 317, 341, 347 

 fertilization in egg of, 164-167 

 Chemistry of the cytoplasm, 58 

 Chiton, egg of, 97 

 Chromatin, increase of, 311 

 Chromidia, 56 



Chromosomes, 6, 49, 50, 310 

 aberrant behavior of, 350-352 

 degeneration of, 56 

 incompatibility of, 351 

 individuality of, 321-324 

 number of, in parthenogenesis, 210 

 role of, in differentiation, 321 ff. 

 Ciona, egg of, 195, 201, 266 

 Cleavage, classification of, 291 

 determinate, 269 

 indeterminate, 269 

 Cleavage-amphiaster, 167 

 Cleavage-asters, 164 



origin of, 182, 183 

 Cleavage-centres, 164 

 origin of, 182, 183 

 Cleavage-cycle, ectoplasmic changes 

 during, 281 

 maximum susceptibility in, 277 

 periods of susceptibility in, 274- 

 277 

 Cleavage-nuclei, types of, 180 

 Coelenterata, 300 



Coelenterates, ectoplasm in eggs of, 90 

 Colloid, 43, 44 

 Colloid chemistry, 59 

 Conduction, 358 



in living cells, 119-121 

 Contractility in eggs, 116, 117 

 Contraction, 358 



in living cells, 123 

 Copulation, 155 



in Platynereis, 189 

 Corymorpha, egg of, 283 

 Crepidula, egg of, 283 

 Criteria for normality, 22, 23 

 Cross-fertilization, 21, 57, 198 

 Cryptobranchus, egg of, 180 

 Crystals in eggs, 57 

 Cumingia, egg of, 98, 153, 223 

 Cyclops, egg of, 49, 180 

 Cynthia, egg of, 304 

 Cytolysis in eggs, 228 

 Cytolytic agents, 227, 232 

 Cytoplasm, 8 



chemistry of, 58 



ground-substance, 57 



movements in, 43, 52, 267-270, 

 282, 284, 305, 306, 308 



physical properties of, 58 



role of, in heredity and differen- 

 tiation, 326-330 

 Cytoplasmic inclusions, 8, 52, 53 ff"., 

 269 

 role of, in differentiation, 302 ff. 

 Cytoplasmic reactions, 326 

 Cytoplasmic structure, alveolar theory 

 of, 59-63 



filar theory of, 63 



granular theory of, 63-64 



D 



Dehydration, 125, 244, 245 



Delamination, 301 



Dentalium, egg of, 97 



Description, role of, in biology, 10, 25 



Differentiation, in cells, 247 



ecto-endoplasmic, 8, 47-49, 363 



nucleo-cytoplasmic, 7, 47 



surface-interior, 357 



without cleavage, 216, 217, 218, 

 299 



386 



