730 



Index 



Middle ear, formation of, 423 

 Mitochondria, 43, 521 



cytochrome oxidase and, 540 

 Mitogenesis, 111-115 



biochemical changes in, 112- 



113 

 generation time of, 114^115 

 "latent period" in, 114 

 Mitosis, centrosome, 100 



chromosomal fibers in, 104-105 



birefringence of, 102, 104 



chromosome chemical changes 



in, 95-96 

 chromosome cycle, 94-98 

 chromosome movements in, 98- 



107 

 chromosome reproduction in, 



96-97 

 chromosome structural changes 



in, 94-95 

 chromosomes in interphase nu- 

 cleus, 97-98 

 cytoplasmic changes in, 109- 



110 

 description of, 91-94 

 differential, 109 

 hormonal effects on, 113 

 inhibition of, 116-117 

 kinetochore in, 103-104 

 metabolism of, 110-111 

 metakinesis in, 105-106 

 modification of, 117 

 nucleolus in, 98 

 spindle in, 101-103 



and astral fibrilization in, 

 52 

 See also Cell division. 

 Mitotic activity in CNS, 373 



dorsoventral differential of, 

 375 

 Modulation, 383-386, 387, 391 



of neurons, 385 

 Molecular ecology, 27 

 Molecular population, 376 

 Mollusks, progressive differentia- 

 tion in, 318-320 

 Molting, humoral control of, 342. 



343, 638, 641 

 Morphogenesis, physical-chemical 

 considerations of, 59-61 

 See also Development. 

 Morphogenetic field, 279-282 

 chorda-mesoderm ("organ- 

 izer"), in, 239, 240, 242, 

 279-282 

 of eye-forebrain, 252-253 

 gradient of egg, 234 

 induction of, 250, 280 

 in neurula mesoderm, 248 

 in regeneration, 677-678 

 regulation of, 63-64 

 self -organization of. 279-281, 



284 

 size related to patterning, 

 281-282 



Morphogenetic movements in 

 gastrulation, 234-235 

 as organizing factors, 235- 

 238,241,281 

 Morphogenetic potential, 243, 



248, 278, 283 

 Morphogenetic processes, 59-61 

 Morphology, new form of, 29, 30 

 Motor cells, 377, 389 



selective excitation of, 384 

 Motor coordination, 392 

 Motor fiber, predestination of, 384 

 Motor neurons, 381, 362, 384, 385, 

 391 

 specification of, 384 

 Motor performance, 391 

 Motor roots, 362, 368, 382 

 Motor unit, 360 



Mouse, fusion of vertebrae in, 701 

 hereditary bleb formation in, 



710 

 hereditary tail abnormalities in, 



700, 702 

 shaker-short mutant of. 708 

 x-ray as teratogenic factor in, 



701 

 See also Dwarf mouse. 

 Mouth, determination of, 263-264 



induction of, 454, 455 

 Movement, integrated. 386 

 Muscles. 361, 362. 363. 369. 381. 

 383, 384, 385 

 denervation of, 361. 368 

 extra set of, 384, 386 

 fibers of, 360 



phylogenetic relations of, 351 

 regeneration of, 690 

 transplantation of, 384 

 Myelin, 347, 349, 367. 375. 388 

 Myelin sheath, 350 



laminated structure of. 367 

 Myelinization, 367 

 Myotomes, segmental arrange- 

 ment of. 372 

 "Myotopic" function. 384 



Nasal cartilages, formation of. 



424 

 Nasal passageways, shaping of. 



424 

 Nasal placode, dependency in ori- 

 gin of, 308 

 differentiation of, 423 

 induction of, 423-424 

 Natural antibodies, development 



of, 564 

 Natural auto-antibodies, concept 

 of. 566-567 

 of egg and sperm, 566, 567 

 Naturphilosophie, 8-1 3 



Goethe. 8, 9, 10, 11. 13, 21 

 von Baer, 11, 12, 13, 14, 16, 21 

 Neoblasts, 667 



Neoteny and amphibian meta- 

 morphosis, 633, 634, 655 



Nephric duct, caudal growth of, 

 467 

 origin of, 466-467 

 territory influence on, 467 

 Nephric fields, 310 



differentiation effects of, 464, 

 465 

 Nephric system, developmental 

 plan of, 463 

 units of, 462 

 Nephrogenic areas, topographic 



localization of, 462-464 

 Nerve, cranial, 361, 383, 386 

 cross unions of, 363 

 deflection toward growing or 



gans, 358-359 

 degeneration of, 358 

 regeneration of, 349-350 

 fiber niunbers in. 369 

 repetition of, 364 

 stereotypism of, 361 

 transection of, 349 

 Nerve branches. See Branches, 



nerve. 

 Nerve cell body, size of, 365 

 Nerve cells, 370 



immigration of, 375 

 Nerve conduction, 363, 376, 385 

 salutatory theory of, 367 

 velocity of, 347 

 Nerve connections, intracentral. 

 359, 391 

 peripheral. 361-363 

 terminal, 361,362-363 

 Nerve cord, diameter of, 375 



early morphogenesis of, 371- 

 372 

 Nerve courses, deflection of, 359 

 Nerve fibers, 352 

 atrophy of, 365 

 bundles of, 367 

 caliber of, 365 

 cell body of, 350 

 constriction of, 363 

 deviation of, 356 

 diameter of, 363, 367 

 filopodia of, 352 

 intemuncial, 359 

 intracentral, 350 

 invasion of, 381 

 orientation of, 351 

 outgrowth of, 349, 356 

 "pioneer," 351 

 recurrent, 356 

 resorption of, 361 

 sympathetic, 362 

 tracts of, 347. 357 



longitudinal, 359, 366 

 "Nerve modulation," 384 

 Nerve orientation. 352 

 Nerve patterns, 358-361 

 Nerve roots, segmental arrange- 

 ment of, 372 

 Nerve stump, 349, 350, 352, 353, 

 357, 358, 362 



