370 



INDEX 



determination of, 321; role of 

 external factors in, 317, ff.; with- 

 out cleavage, in Chcetopterus, 279, 

 279 



digametic, females, 314; males, 314 

 Dileptus, nuclear division, 58 

 diploid number of chromosomes, 133 

 Diplozoon, 107 

 direct cell division, 43 

 discoblastula, 220, 331, 332 

 Discoglossus, spermatozoon, 100 

 dispermy, effect upon differentiation, 

 300; evidence from, upon chromo- 

 some hypothesis, 301 

 distributed nucleus, 5859 

 Dixippus, X-chromosome; 312 

 Dobell, 58 



Doliolum, budding, 7 

 dominance, in embryo hybrids, 305 

 Drago, 167 

 Drew, 106 



Driesch, 263, 264, 281, 301, 305 

 Dromia, cleavage (superficial), 242 

 dyads, 138 

 Dzierzon, 315 



Echinoderm, polarity of ovum, 92 

 Echinus, cleavage under pressure, 



284 ; development in chemically 



altered media, 320; of 



isolated blastomeres, 281 ; number 



of ova, 107 

 ectoblast, 334 

 ectoderm, 334 

 ectoplasm, 34, 267 

 ectosarc, 34 

 Edwards, 311, 313 

 eggs, care of, 104; see also ovum. 

 egg membranes, 95, ff.; as related to 



conditions of development, 108 

 egg tubes, of Insects, 117, 118 

 Elasmobranch, blastoderm, 355 ; 



blastula, 344: gastrulation, 343, 



ff; 344 



emboitement, 22 

 embryo, formation from germ ring, 



347, 352 

 Embryology, defined, 2; phases in 



history of, 20-21 

 endoderm, 334 

 endogamy, 189 

 endoplasm, 34, 90, 267 

 endosarc, 34 



end piece, of spermatozoon, 100 

 Entamoeba, autogamy, 191, 192 ; 



maturation, 157 

 enteroccelic grooves, 336 

 enteroccels, in Elasmobranchs and 



Reptiles, 347; in frog, 342 

 enteroderm, 348, 350 



enteron, 336 



entoblast, 334 



entrance disc, of Nereis, 169 



Ephelota, budding, 7 



epiblast, 334 



epiboly, 336 



epigenesis, 22, 23 



equational division, in maturation, 



152 



equatorial plate, 52 

 Equisetum, multipolar spindle, 57 

 Esox, micropyle, 96 

 Ethusa, spermatozoon, 99 

 Eudorina, reproduction, 199 

 Euglena, nuclear division, 61 

 Euglypha, nuclear division, 60 

 Eunice, spawning season, 103 

 Euplotes, fission, 6 

 Euschistus, dimorphic spermatozoa, 



101 



evagination, 360 

 exogamy, 189, 200 

 exoplasm, 90; of ovum, during 



fertilization, 174, 175 

 external conditions, as factors in 



differentiation, 318, ff. 



Farmer and Moore, 133 



fertilization, 13, 164, ff.; among 

 Protozoa, 189, ff.; by ''foreign" 

 spermatozoon, 171, 172; chemical 

 processes of, 205-206; defined, 

 165; following maturation, 187- 

 188; membrane, 175; - - arti- 

 ficial formation, 205; mutual, in 

 Ciliates, 194; of enucleate egg- 

 fragments, 301-303; preceding or 

 during maturation, 180, ff.; re- 

 lation to heredity, 214, ff.; 



rejuvenation, 209, ff.; 212; 



- reproduction, 17, 202, 

 '., 208, ff.', variation, 



!13; selective, 171; significance of, 

 202, ff.; time relation to matura- 

 tion, 179, ff., 180 



filar substance, 34 



fission, in Metazoa, 4-5; multiple, 3; 

 simple or binary, 2, 5 



flagellum, of spermatozoon, 98 



Flemming, 43, 44, 141 



Fol, 80 



follicle, of ovum, 96; ovarian, 119- 

 120, 119 



formative stuffs, 278 



frog, blastula, 340; development of 

 single blastomeres, 284285; en- 

 terocoals, 342 



Frontonia, nucleo-cytoplasmic rela- 

 tion during interkinesis, 78 



Fundulus, chromosomes, hybrids in 



