SUBJECT INDEX 



763 



Spectra, action, of phototaxis, 384-388 

 fluorescence, 343, 364-370 

 of chlorophylls, 364-370 

 of photosj-nthetic bacteria, 378-380, 



384-388 

 of phycobilins, 343, 364-370 

 of red algae, 364-370 

 in study of energy transfer (see 

 Energy transfer) 

 reflection, 343, 348-351 



of leaves and algae, 348-351 

 measurement, 346-348 

 transmission, 346-348 

 Spectral sensitivity, 621, 664-667 

 of Cerianthus, 628 

 of crustaceans, 665 

 of Echinaster, 659 

 of Eledone, 642, 664 

 from eye-pigment migrations, 670 

 of fireflies, 670 

 of insects, 665-666 

 of leeches, 665 

 of Limulus, 651, 665 

 of Lithobius, 666 

 of protozoans, 625-627 

 of turbellarians, 629 

 Spectroscopic instruments, 202-213 

 angular apertures, 209 

 aperture ratio, 209 

 collimator for, 202-207 

 / number, 209 

 monochromator, 202 

 grating, 204-207 



prism compared to, 203, 210 

 optical systems, 212 

 spectrograph, 202 

 spectroscope, 202 

 condenser, 208 

 optical sj^stems, 211, 212 

 transmission, 208 

 spectroscope prism, 202 

 use for irradiation, 212 

 Spectroscopic moment vectors, 102 ff. 

 predicted and observed directions in 



porphins, 104, 107 

 values, for benzene substituents, 107 

 for porphin substituents, 108 

 Spectroscopic transitions, allowed, 74-75 

 90 

 criteria for assignment, 77, 90, 103 

 energies, 74 



forbidden, 75-76, 90, 100 

 polarizations, 76, 91, 94, 95, 103, 105 

 Sphere, Ulbricht, 347, 348 

 Sphodromantis, growth of compound eye 



653 

 Spiders, visual performance, 669-670 

 Spin-orbit coupling in molecular spectra, 

 85 



Spinach, 353 



Spinther, compound eyespots, 635 

 Spondyhis, ocelli, 639 

 Sporobolus, 531 

 Square-well potential, 73 

 Squid (Loligo), 623-624, 642 

 Standard, of absorption, 252-253 

 black-body, 244 

 candle, 137 



color temperature, 248-250 

 colored glasses, 252 

 colored solutions, 253 

 complete radiator, 244 

 lamp, 244-250 

 luminance, 137 

 luminous intensitj^, 247 

 radiant intensity, 246-247 

 transmission, 252-253 

 wave length, 251 

 Standard carbon-filament lamp, 263 

 Standard Observer, 137 



ICI coefficient, 137 

 States of a molecule, 79-81 



degeneracy and angular momentum, 99 

 first excited, 85, 86 

 nomenclature, 80, 81, 98-102 

 removal of degeneracy, 101 

 Stefan-Boltzmann law, 149 

 Stenopkragma, 534 

 Stentor, photosensitivity, 626 

 Steradian, 137 



Steric hindrance, effect on spectra, 72 

 Stigma, definition, 624 

 of Chlamydomonas, 626 

 of Gonium, 627 

 of V^lvox, 627 



Stigmata, in protozoans, 626-628 

 Stilbene, 87 

 Stimmung, 465 



Stimulus, in photobiological processes, 

 295 

 transmission, 465 

 Stomatal movements, 445 

 Strepsiptera, aggregated ocelli, 646 

 Streptococcus varians (Rhodopseudomonas 

 spheroides), 373, 374, 382, 384 



Strongylocentrotus, photic responses, 661- 



662 

 Styrene, 95 

 Substituents, effect on spectra, 88, 89, 



102 ff. 



Substitution, chemical, effect on spectra, 

 88, 89 

 at side of conjugated system, 94 

 spectroscopic moment vectors, 102 ff. 



Succinic acid, 316, 319, 320, 323 



Sugar cane, agricultural yield, 277 



Sulfur, 298 



