408 
Motion, difference between plants 
and animals, 370. 
Mule, transverse stripes in the, 
100. , 
Miller, Erik; eye lens in the 
tritons, 28. 
Miller, G. E.; 
clock, 382. 
Mus decumanus, Mus rattus, Mus 
sylvaticus, 90. 
Myxomycetes, 29, 372. 
stopping of a 
Nageli; idioplasmic network, 
230; unfolding of the anlagen 
of the idioplasm, 239; Weis- 
mann’s objection, 242, 243; 
general and mnemonic idio- 
plasm, 255; the mnemonic 
phenomenon, 316. 
Nature, former habit, 384. 
Navicula brevis, reaction to light, 
372. 
Neal; acclimatization, 372. 
Nerve cells, 262. 
Nervous energy, 20, 33, 41, 43, 
45, 46, 48, 49, 50, 70, 77, 79, 86, 
98, 256, 289, 299, 319, 330-332, 
336, 340, 344, 357. Specific, 62- 
63. 
Nervous coordinations, 45, 251, 
252, 253. 
Nervous current, nervous flux, 
32, 35, 36, 37, 39, 41-43, 102, 
295- 297, 290, 300, 319, 322, 325, 
346, 347, 348, 356; compared 
with electric, 289-292; specific, 
16, 102, 290, 374; oscillating, 
341 ff. 
Nervous discharge, 41, 202 ff, 
322, 342, 343, 346, 348, 352, 357. 
Neuters among the insects, 178, 
187, 312. 
Index 
Newts, arrests of development 
of, 99; regeneration in, 19, 140. 
Nisus formativus, 137. 
Nostalgia, 383. 
Nuclear division, 79, 83, 92, 132, 
246, 283, 350, 354. 
Nuclear somatisation, 18, 24-26, 
27, 79, 83, 84, 89, 92, 119, 262, 
297, 290. 
Nuclei, somatic and germinal, 84, 
85. 
Nussbaum; division of Infuso- 
ria, 54; form-determining en- 
ergy, 50; continuity of the 
germ cells, 189; inheritance of 
acquired characters, 190. 
Ollier; transplantation of bony 
tissues, 90. 
Omphalosite monsters, 113, 114. 
Ontogenetic stimulus, 51, 59, 94, 
IOI, 306, 309. 
Optimum conditions, 
towards, 372. 
Orr; alteration of the nature of 
growth, 96; crosses, 100; bio- 
genetic theory, 251-256; com- 
parison with the mnemonic 
phenomenon, 316; vital phe- 
nomenon, 332. 
Osborn; phagocytes, 49; influ- 
ence of fasting on transforma- 
tions, 50; adaptive reactions, 
209; latency, 217; colors in 
pleuronectids, 217. 
Osmotic currents, 270. 
Ostwald; term “stationary,” 361; 
pleasure, 395. 
Overcrowding, effects of, 197. 
Ownership, sense of, 387. 
tendency 
Pangenetic theory, 206. 
