878 



Index 



MuscleCs), classification of, 576 

 conduction in, 584, 587 

 contraction time, 584, 586 

 electron microscopy of, 577 

 fast and slow responses in, 597 

 fibers, types of, 581, 582 

 frequency of stimulation of, 592 

 gross functions of, 576 

 heart, effects of electrical stimulation 



on, 565 

 hemoglobin in, 292 

 histological types, 580 

 inhibition in action of, 805 

 innervation, multiple, 595 



inhibition by, 597 

 iterative, 592 



microscopic histology of, 578 

 non-iterative, 592 

 origin of cardiac beat in, 546 

 phosphagens of, distribution of, 615 

 propulsion of food by, 149 

 red, 582 



relaxation rates of, 584, 586, 601 

 repetitive excitation in, 592 

 rhythmic activity in, 605 

 sense receptors, adaptation in, 512 

 smooth, conduction in, 590 

 striations in, 578 

 summary, 621 

 time constants of, 584, 586 

 time relations of, 577 



histological correlations, 577 

 tonus of, 601 

 transmission of impulse to, chemical 



agents in, 608-614 

 use of in feeding, 145 

 visceral, effect of drugs on, 606 

 viscosity of, 602 

 white, 582 

 Mussel, electrocardiogram from, 555. See 



also Mytilus. 

 Mya, motor innervation in, 601 



photoreception in, 406 

 Myelination of nerve fibers, speed of con- 

 duction and, 785 

 Myoglobin, 292 



absorption spectra of, 298 

 Myopia, 395 

 Myosin, 578 



Myoxocephahis, chloride excretion in, 94 

 Mytilus, blood chloride in, 88 

 cilium in, 644 

 muscle relaxation in, 603 

 osmotic adjustment in, 12, 13 



Naphthoquinone, methyl phytyl, 132 

 Neanthes virens, osmotic regulation in, 17 

 Necturus, kidney in, 54 

 Nematocyte, 656 

 Nematocysts, 655-658 



Nemertea, oxygen supply of, 211 

 Neocortex, 835 



Neoechinorhynchiis imydis, osmoregula- 

 tion in, 18 

 Nephridia in earthworm, 37 

 Nephron, vertebrate, schematic representa- 

 tion, 48 

 Nereis, brain in, 817 



osmoregulation in, 14, 15, 16, 17, 18 

 peristaltic locomotion in, 813 

 Nereis cultrifera, osmotic adjustment in, 12 

 Nereis diversicolor, hemoglobin function 



in, 322 

 Nereis pelagica, osmotic adjustment in, 12 

 Nerophis, osmoregulation in embryo of, 19 

 NerveCs), control of respiration by, 254 

 control of thermostimulation by, 365 

 motor, muscular conduction and, 587 

 optic. See Optic nerve. 

 regulation of hearts by, 557 

 stimulation of secretion of fluids by, 156 

 transmission of hearing impulse by, 480 

 transmission to muscle, chemical agents 

 in, 608, 614 

 Nerve action potentials, ionic basis of, 780 

 Nerve centers, "spontaneous" activity of, 

 805 

 asynchronous, 806 

 synchronous, 807 

 Nerve fibers, diameter of, speed and, 782 

 electrical phases in, 778 

 giant, 786 



length of, speed and, 782 

 myelotropic, 785 

 nodes in, 786 



sheath of, speed and, 784, 785 

 speed of conduction in, 782 

 Nerve impulse, auditory, 477 

 nature of, 777-781 

 in photoreception, 428 

 Nerve nets, 808 



Nervous conduction, interneuronic trans- 

 mission in, 789 

 Nervous systems, 776-862 

 conduction in, 777-808 



speed of, 782 

 development of, 848 

 endocrine activity' of, 768 

 peripheral vs. central, 809 

 persistent phenomena in, 841-847 

 rhythmic activity in, 806, 807 

 summary. of, 847 

 Nervous tissue, acetylcholine and cholin- 



esterase content, 792 

 Nets, nerve, 808 

 Neuromuscular facilitation, 594 

 Neuromuscular junctions, 587 

 Neuromuscular transmission, chemical 



agents in, 608-614 

 Neurones, contiguity between, 789 



