INDEX OF SUBJECTS 



329 



altered by alkaloids, 126 sqq. ; in- 

 dependent of sulphates, 144; 

 without potassium, 146; without 

 magnesium, 147 ; in neutral 

 media, 151 ; alteration of egg 

 structure in, 80, 163, 222, 232, 247- 

 251 ; two processes involved in, 252. 



Film, at surface of blastomeres, 45, 54, 

 150 ; of drops of fluid, 42, 45, 54. 



Final cause, see Cause. 



First furrow, coincidence of, with 

 sagittal plane, see Furrow, first. 



Fissure, choroid, 273. 



Flattening of blastomeres against one 

 another, 45, 53. 



Flexure, cranial, 110. 



Folds, medullary, see Medullary. 



Follicle cells, in Tunicata, 5. 



Follicles, of hair, 7. 



Food, growth dependent on, 2, 58, 59. 



Foot, rate of growth, 70. 



Form, production of, 1 ; nucleus 

 necessary for, 252, 254. 



Formal cause, sec Cause. 



Formate of sodium, 145. 



Formative stimuli, 273. 



Fovea germinativa, 79. 



Fragments of egg, see Egg-fragments ; 

 of blastulae, and gastrulae, see 

 Blastulae, Gastrulae. 



Framboisia, 135. 



Freedom, 289, 299. 



Freshwater, Fundnluseggs in, 117,136. 



Frog, ovarian and uterine egg, 79 ; 

 effect of fertilization, 163 ; eggs 

 forcibly inverted, 18, 78, 158; in- 

 fluence of gravity upon, 18, 78 sqq. ; 

 eggs placed on vertical wheel, 85 ; 

 eggs kept in constant motion, 86 ; 

 egg centrifugalized, 29, 87, 88 ; 

 pressure experiments, 34-37, 40, 

 168; absorption of water by tadpoles, 

 58; eggs exposed to electric cur- 

 rents, 92, 93 ; eggs, influence of 

 light on, 94 ; eggs, influence of heat 

 on, 97-99; of cold on, 99-100; 

 eggs, respiration of, 1 10-112 ; effect 

 of sodium chloride on eggs, 119, 120, 

 276 ; of other substances, 120, 121 ; 

 acclimatized to sodium chloride, 

 136 ; first furrow and sagittal plane, 

 17, 159, 165-168; half-embryo 

 from half-blastomere, 18, 159 sqq., 

 169-171 ; double monsters, 171, 

 172 ; development of animal and 

 vegetative blastomeres, 173 ; forma- 

 tion of lens,275,276 ; of cornea, 276, 

 277. 



Frontal breadth in Carcinus, growth 

 of, 71 ; variability of, 72. 



Fuchsin, 94. 



Functional adaptation, 290. 



Fundulus embryos, in light and dark- 

 ness, 94 ; need of oxygen for, 111, 

 114, 274; in fresh water, 117; 

 effect of ions on, 135, 136 ; in 

 sodium chloride, 117 ; in magne- 

 sium chloride, 276 ; first furrow 

 and sagittal plane, 178 ; injuries 

 to blastopore, 178. 



Furrow, first, and sagittal plane in 

 Frog, 17, 159, 165-168 ; in Necturus, 

 168 ; in Newt, 175 ; in Fishes, 178 ; 

 in Ascidia, 229, 233, 235 ; in 

 Echinoids, 250 ; and plane of sym- 

 metry, 167, 233; and horizontal 

 plane in Newt, 175 ; first and en- 

 trance point of spermatozoon, 40 ; 

 in Frog, 247, 248 ; in Toxopneusies, 

 250. 



Furrows, polar, parallel, and crossed, 

 25, 26, 46, 47 ; in Rana, 53 ; in sys- 

 tems of oil drops, 50. 



Fusion of cell-aggregates, sec Cells, 

 movements of ; of larvae to form 

 double monsters, 137, 201 ; or one 

 larva, 202. 



Galvanotaxis, 272. 



Galvanotropism, 272. 



Gammarus, 24. 



Ganglia, see Nerve. 



Ganoids, 26. 



Gastrula, of Echinoderms, 5 ; 

 opaque in neutral media, 151 ; of 

 animal and vegetative cells, 191- 

 194 ; pieces of, in Echinoids, 194 ; 

 of Ascidia divided, 238. 



Gastrula wall of lithium larvae, 

 138-140. 



Gastrulation, need of sodium for, 145 ; 

 of isolated blastomeres, 191-194. 



Gemmule of Sponges, 5, 11. 



Genetic restriction, 246, 277; sec 

 also Potentialities, limitation of. 



Geophilus, 4. 



Geotropism, 272. 



Germ-bands, 5 ; of Clepsine, 6 ; from 

 teloblasts, 29 ; of Crustacea, 34. 



Germ-cells, liberation of, 11 ; the 

 vehicles of inheritance, 1, 252 ; of 

 Ascaris, 253. 



Germ-layers, 2. 



Germ-ring, injuries to, 178. 



Germinal localization, His's prin- 

 ciple of, 17. 



Germinal value, and loss of potenti- 

 ality, 181 ; and number of cells, 

 182, 197, 206, 269; and size of 



