754 



RADIATION BIOLOGY 



Light, quantity, 524 



red, 525-527 



stimulating, definition, 520 



units, 135, 137 



velocity, 130-131, 262 



yellow, 525-527 

 Light adaptation, 664 

 Light sensitivity (see Photosensitivity) 

 Ligia, ey#'pigment migration, 669 

 Ldmax, circus movements, 640 

 Limulus, dark adaptation, 664 



detection of polarization plane, 654 



flicker fusion, 668 



intensity discrimination, 669 



inverted swimming, 644 



nerve impulses, 651 



ocellus, 634 



peripheral basis for hue discrimination, 

 650-651 

 Lineus, photosensitivity, 631 

 Linum, 528 



Lilhobius, spectral sensitivity, 666 

 Littorina, photosensitivity, 640 

 Logarithmic growth, 275 

 Loligo, 623-624, 642 

 Longuet-Higgins theorem on twisting of 



double bonds, 87 

 Lophopus, photosensitivity, 637 

 Lumbricus, photosensitivity, 635 

 Lumen, definition, 137 

 Luminal, chemiluminescence, 54 

 Luminescence of meteors, 42 



(iSee also Chemiluminescence; Fluores- 

 cence; Phosphorescence) 

 Luminous energy, 126-128 

 Lux, 137 



Lymantria caterpillars, intensity discrimi- 

 nation, 669 

 Lythrum, 528, 534, 536 



salicaria, 523, 524, 526, 528 



M 



Magnesium compounds, ether-soluble, 

 407, 413 



in etiolated leaves, 423 



photochemical formation, 416, 418, 

 423, 434 

 Magnesium protoporphyrin, 434 

 Magnesium vinylpheoporphyrin-as, 434 

 Malic acid, 298, 318-320, 323 

 Malonate, 320 

 Malva, 463 

 Manometer, 280-283 



calculations, 271 



one-vessel, 272, 280 



shaking rate, 272 



two-vessel, 280 

 Manometric apparatus, 272 



Manometric method, 269, 273, 288 

 Marthasterias, neural connections to 



ocelli, 660 

 Mass spectrometer, 268, 274 

 Matching of backgrounds, by insects, 

 667-668 



by Misuniena, 667 

 May flies, compound eyes, 652 

 Median ocelli of crustaceans, 644 

 Melanoplus, dark adaptation, 664 

 Mercury, photosensitization reactions, 

 with hydrogen, 47 

 with sodium, 39 

 with thallium, 38 

 Mercury arc, 173-176 



application, 176 



capillary, 174 



concentrated arc, 175 



high-pressure, 174 



low-pressure, 174 



medium-pressure, 174 



operation, 175 



short arc, 175 



spectrum, 173 

 Mercury hydride, in quenching reactions, 

 47 



persistence of rotation, 24 



rotational quanta, 20 

 Mesocotyl, 463 

 Metabolic drift, 535 

 Metal complexes of porphyrins, 85, 101, 



108 

 Metastable system, 543 

 Methylene blue, 323 

 Methylurea, 323 

 Michler's hydrol blue spectrum, 73, 79, 



91-93 

 Microcalorimeter, 280, 281 

 Microscopic reversibility, 5, 52 

 Mimulus ringens, 523 

 Mirrors, 140, 207 



astigmatism, 142 



parabolic, 142 

 Misumena, matching of backgrounds, 667 

 mks units, 135 



Mnemiopsis, photosensitivity, 629 

 Modulator elements, retinal, 603-605 

 Molecular complexes, 115 

 Molecular orbital method, 71 

 Molecule, excited, 543 

 Monochromators, aperture ratio, 209 



collimator, 211 



condensing systems, 208 



focusing systems, 207 



grating, 204, 210 



for irradiating biological material, 211 



prism, 202, 203, 210 



transmission, 251 



