332 



INDEX OF SUBJECTS 



Lepidonotus, 25, 46. 



Lepidosteus, 26. 



Light, general effect on developing 

 organisms, 93 ; on fern prothallus, 

 272 ; on Serpula, Sertularella, 272 ; 

 effect on direction of embryonic 

 axes, 93 ; of various colours on 

 eggs of Echinus, Planorbis, 94 ; 

 liana. 94, 95 ; Trout, 95 ; Limnaea, 

 95 ; Echinoid larvae, 96 ; promotes 

 oxidation, 112. 



Limax, segmentation of, 25, 26, 30 ; 

 spiral asters, 40. 



Limbs, buds of, in Vertebrates, 11. 



Limitation of potentialities, see 

 Potentialities. 



Limnaea, 67. 



Linear cell aggregates, 5. 



Liriope, 181. 



Lithium chloride, eggs of Amphibia, 

 120, 135; salts, on Amphibian eggs, 

 120, 133, 135 ; on Echinoid larvae, 

 137-140, 146. 



Littorina, 71, 72, 74. 



Lobe, polar, 214, 228 ; removal of, 

 217, 224, 227. 



Localization of ontogenetic effects, 

 289. 



Loss of potentialities, see Potentia- 

 lities. 



Lucifer, 22, 47. 



Macromeres of Echinoids, 22, 30, 

 185, 192; of Ctenophora, 211; of 

 Mollusca, 215, 221. 



Magnesium in artificial partheno- 

 genesis, 123 ; Frog embryos, 133, 

 135 ; Fundulus, 135, 276 ; Arenicola 

 larvae, 135 ; effect on ciliary and 

 muscular movement, 135 ; necessity 

 of, 147. 



Magnetism, 91 sqq. 



Male element, function of. according 

 to Aristotle, 13. 



Mammalia, blastocyst, 2, 6, 7, 115 ; 

 truncus arteriosus, splitting of, 6 ; 

 trophoblast of placenta, 7; embry- 

 onic plate, 9-; segmentation in, 24. 



Man, see Human being. 



Massive cell aggregates, 11. 



Material basis of inheritance, 1, 19, 

 252 ; cause, see Cause ; explanations 

 of ontogeny, 12, 20, 286-289, 290, 

 296, 298. 



Materialism, 301. 



Matter and material cause, 13. 



Matter and mind, 301. 



Maturation, nuclei of germ-cells in, 

 252, 254. 



Maximum temperature, see Tempera- 

 ture. 



Mechanical, see Mechanism ; Mechan- 

 ical agitation, 89. 



Mechanism of inheritance, 1, 280 ; 

 mechanism, explanation of onto- 

 geny as a, 12, 20, 286-289, 290, 292, 

 296, 298. 



Medulla, roof of, 7 ; solid, in Frog's 

 embryos grown in certain solu- 

 tions, 133. 



Medullary folds, 9 ; not formed at 

 low temperatures, 104 ; divided at 

 high temperatures, 99 ; remain 

 open in various solutions, 119 sqq.; 

 in Hemiembryo, 160. 



Medullary plate of Amphioxus, 8. 



Medusa from isolated blastomere. 

 181. 



Megalecithal eggs, 24. 



Membrane of egg, 45, 46 ; absence, 

 due to poisons, 128 ; formed by 

 chloroform, 129; at surface of cells, 

 see Film ; of shell, 104; of Descemet, 

 276. 



Mendelian allelomorphs, 266. 



Mercury, 132. 



Meridian, streaming, in inverted 

 Frog's eggs, 84. 



Meridional division, 22, 32 ; see also 

 Cell-division. 



Meridional polarization in Frog's egg, 

 83. 



Meroblastic segmentation, see Seg- 

 mentation. 



Merogony, 131 ; male nucleus only in, 

 254 



Mesenchyme, of Echinoderms, 5 ; of 

 Echinoids, 185, 261, 262, 269; of 

 partial larvae, 193, 194, 198. 237 ; 

 of Ascidia, 235 ; of Echinoids, 

 displaced, 274. 



Mesoderm, segmentation of, 11 ; in 

 Hemiembryo, 160 ; deficient, after 

 injury to germ-ring, 179 ; depen- 

 dent on presence of polar lobe, 217. 



Mesomeres in Echinoids, 27, 185, 192. 



Mesonephric tubules, see Kidney. 



Metabolism, nucleus needful for, 252, 

 254. 



Metamorphosis (Harvey), 14. 



Metanephric blastema, see Kidney. 



Methods of embryology, descriptive, 

 12 ; experimental or physiological, 

 13. 



Micromeres in Echinoids, 22, 30, 185, 

 192 ; suppressed by pressure, 37, 

 186 ; by heat, 186 ; in ' spiral ' eggs, 

 25 ; suppressed by pressure, 39, 

 213 ; rotation of, 29, 47 ; of Mollusca 



