INDEX 



835 



Sphenodon punctatus. 

 fvmdus, PI. VIII 

 iris, 381 

 parietal eye, 715, 716, 718 



function of, 719 

 pineal apparatus, 714, 715 

 pupil, contractile, 612 

 retina, 382, 610 

 visual acuity, 661 

 cells, 382 

 Sphincter pupilla? muscle, characteristics in 

 anurans, 337 

 birds, 407 

 lacertilians, 357 

 monotremes, 436 

 placentals, 468 

 selachians, 285 

 snakes, 387 

 Sphenodoti, 381 

 teleosteans, 303 

 Sphyrna tiburo, 327 

 eyelids, 289 

 eyes of, 327 

 zygcena, 327 



extra-ocular muscles, 327 

 optic pedicle, 290 

 Spiders, 213 



cave-. See Anthrobia. 

 garden-. See Araneus. 

 house-. See Tegenaria. 

 jumping, conditioning of, 580 

 vision of, 580 

 See also Evarcha, Salt ic us. 

 ocelli of, 139, 140, 149, 150, 213 

 ripple-, vibrotropism in, 579 

 web -spinning, menotaxis in, 61 

 vibrotropism in, 579 

 vision of, 579 



See also Araneus, Tegenaria. 

 wolf-. See Lycosa. 

 Spilotes variegatus, head of, 384 

 Spinachia, colour preference in, 624 

 Spirographis, phototropic movements in, 



39' 

 Spondylus, 201 



ocelli of, 148, 201 

 Sponges, 181 



myo -epithelial cells, 513, 514 

 reactions of, 513 

 See also Leucosoleiiia. 

 Sporozoa, 180 



Springtails. See Collembola. 

 Squalus, 97 



Squalus 



chromatophores, 97 

 eye of, 275 

 ptipils, 285, 287 

 Squatina, 288 

 pupil, 286 

 visual cells, 288 

 Squids, 196 



colour changes in, 85, 93 

 eyes of, 143, 202 

 luininescence in, 740, 746 

 See also Loligo. 

 Squirrel, African, pupils, 472 

 common, 445 



colour vision of, 633 

 pupils, 472 

 retina, 484 



vascularization of, 479 

 visual cells, 482 

 flying. See Flying squirrel, 

 ground. See Souslik. 

 See also Sciuridse. 

 Stalked eyes, in cephaloiDods, 203 

 in fishes, 326, 327 

 insects, 223, 225 

 Starfish, 184, PI. I 

 nervous system, 516 

 reactions of, 516 

 visual organs, 185 

 See also Asterias. 

 Stargazer. See Astroscopus, Uranoscopus. 

 Starling, Ernest Henry, 548, 549 



(bird). See Lamprocolius, Sturnus. 

 Statocysts, in cephalopods, 202 

 in comb -jellies, 182 

 fishes, 74, 76 

 scaphopods, 197 

 tunicates, 228 

 Stato-kinetic reflexes, 667 

 Steatornis, iris, 407 

 Stemmata, 220, 222 

 Stenopoeic pupils, 612 



accommodation and, 641 

 Stenostonum, sense organs of, 189 

 Stefitor, 179, 180 



cceruleus, klmotaxis in, 49, 50 

 photosensitivity of, 125 

 Stephanoaetus, 606 

 Stereoscopic vision, 698, 700 

 Sterria hirundo, 419 



bifoveate retina, 419 

 Stick-insect. See Dixippus. 



