INDEX

The figures in bold face type indicate the number of a page containing an ilhistration in the text; those in italics indicate the number of a page showing a marginal illustration.

Acipenser median eye, 713 Aard-vark, 442, 445 pupil, 317 cornea, keratinized, 456 fulvescens, visual cells, 320 nictitating membrane, 493 ruthenus, 317 pupil, 472 eye, 318 Ablepharus, secondary spectacle, 366, 367 sturio, eye, 275 Abyssal habit, degenerate eyes due to, 722 Acnidaria, 182 Acanthephyra, bioluminescence in, 742,743 See also Coelenterates, Comb-jellies. Acarines, 216 Acone eye, 167 eyes of, 216 Acrania. See Cephalochordata. vision of, 579 Acrida turrita, colour changes in, 94 Accipiter, Miiller's ciliary muscle, 406 Acrobates. See Flying phalanger. orbit, 423 Actinia, phototactic reactions of, 571 Accommodation in invertebrates, 590 Actinopterygii, 234, 235 in vertebrates, 640 Acuity of vision. See Visual acuity. amjahibians, 647 Adiposo -genital dystrophy, 560 ainphibious animals, 654 Adrenal gland, hormones and, 550 birds, 651 Aedes, scototaxis in, 60 chelonians, 651, 652 Aegd, telotaxis in, 56 crocodilians, 651 Aeglina prisca, 157 cyclostomes, 644 eyes of, 157 lacertilians, 651 Aeschna, 225 mammals, 652, 653 larvae, optic ganglia, activity of, 524 sauropsidans, 649, 650 optomotor response of, 589 selachians, 647 califoniica, 222 snakes, 648 Esthetes, in Chiton, 196 teleosts, 645, 646 Agama agama, 359 dynamic, 644 iris, 359, PI. V muscle of, in Alciopa, 591 Agaricus olearius, bioluminescence in, 737 in cephalopods, 590 Aggregate eyes, 151 in snakes, 387 Agnatha, 233 See also Ciliary muscles, jiineal organ in, 713 pecten and. 416 See also Cyclostomes. static, 640 Agwantibo, 443 structure of retina and, 656 See also Lemuroids, Priniates. Acerentomon, 218 AhcetuUa picta, iris, 387 Achias rothschildi, 223 Alaurina prolifera, ocelli of, 188 Acholoe, bioluminescence in, 742, 744 Alburnus, colour preference in, 624 Acilius larva, tlermal sensitivity, 114 lucidus, migration of pigment in, 615 eye and cerebral ganglion, 519 visual pigments, 121 Acipenser, 315 Alcedo, 417 anterior chamber, 319 bifoveate retina, 417 choroid, 319 vision of, 641, 655 780 INDEX

Alciopa, 192 Amphibians, colour changes in, 82 accommodation in, 591 control of, 97, 558 ocelli of, 143, 192 mechanism of, 86 Alligator, 375 pineal organ and, 719 brain, 533 rhythmic, 20 visual acuity, 665 colour vision in, 627 field, binocular, 682 ojitomotor reaction and, 623 chinensis, fundus, PI. VIII dermatoptic sensitivity of, 32 mississippiensis, visual cells, 377 eyes of, 334 j^. Allolohophora, conditioning of, 573 degenerate, 726, 730 Alouatta. See Monkey, howling. fore-brain, 543 Alytes obstetricans, 334 removal of, 545 colour blindness of, 628 iris, contraction to light, 89 pupil of, 339 lateral geniculate body, 541 Amhlyomma pomposum, 217 mid-brain, 535 Amblyopsidse, 725 migration of retinal pigment, 614 Amhlyopsis, degenerate eyes in, 726 visual cells, 616 Amblyrhynchus cristahis, 356 movement, perception of, 705 Ambystoma tigrinum, 334, 346 neuro -endocrine system, 557 eyes of, 346, 728 nocturnality of, 603 larva. See Axolotl. ocular movements of, 694 Ameiurus, 307 optic thalamvis, 540 colour changes in, 97 pineal apparatus, 714 eyes of, 725 function of, 719 larvae, phototaxis in, 46 primitive, 234, 235 optic nerve, 310 pupillary reactions, 89, 700 visual cells, 307 refraction of, 638 migration of, 616 reproductive cycle in, 17 Amia, 279, 321 rods, thickening of, 611 choroidal gland, 321 spatial judgiuent of, 702 colour vision in, 624 tectum, 534 cornea, 295 telencephalon, 543 eye of, 276, 321 vision of, 599 median eye of, 713 visual acuity of, 661 visual cells, 321 field, binocular. 682 migration of, 614 pathways of, 537, 544 Ammocoetes, 92, 260 I^igments of, 121 colour changes in, 92 See also Anurans, Cfecilians, Urodeles. eyes of, 261 Amphibious eyes in fishes, 324 light-sensitive cells in tail, 132, 263 vertebrates, accommodation in, 654 median eye of, 717 duplicated optical system, 641 optic nerve, 270 Amphioxus, 229 Amtnomanes, camouflage in. 83 cells of Joseph, 229 Ammophila, mnemotaxis in, 79 infundibular organ, 229 Amoeba proteus, 179, 180 nerve-cord, 239^ 530 diffuse sensitivity of, 113 nervous system, 530 photokinesis in, 35 organs of Hesse, 230 Amphibians, 333 vertebrate eye developed from, 244 accommodation in, 647 Amphiporus, 189 brain, 533 ocelli of, 189 transection of, 534 Amphisbcena punctata, degenerate eyes of, ciliary ganglion, 501 733 cochlea, 534 Amphisbaenidse, 733 INDEX 781

Amphisbsenidse, degenerate eyes of, 733 Annular pad, characteristics in AmphitretMS, 203 monotremes, 436 tubular eyes of, 203 snakes, 389 Amphimna, 349 Sphenodon, 381 eyes of, 349 accommodation and, 649, 650 Anahas, accommodation in, 654 Anodonta, 201 Anableps tetrophthalmus, 325 dermal sensitivity in, 114, 574 ciliary processes, 301 eyes absent in, 201, 722 eyes of, 324, 326 Anolis, 361 optics, 642 bifoveate retina, 365, 366 vision of, 641, 655 colour changes in, 87, 98, 105 Anangiotic retina, 480 control of, 558 Anax, dorsal light reaction in, 74 rhythmic, 20 optomotor response, 589 vision of, 629 Ancala fasciata, eyes of, 222 parietal eye, 717 Angle gainma, 673 transparent eyelids, 366 in vertebrates, 676, 677 alligator, eyelids, 366 Anguilla, 46 fundus, 361, PI. VI colour changes in, 96 argenteolus, eyelids, 367 cornea, 295 carolinensis, reproductive cycle in, 17 growth of eye of, 273 lucius, eyelids, 367 migration of rods, 614 Anomalops katoptron, luminous organ in, optic nerve of, 311 737, 738 phototaxis in, 46 Anopheles, scototaxis in, 60 retinal vascularization, 300 Anophthalmus, dermal sensitivity in, 114 viveal tract, 299 eyes lacking in, 724 Anguis fragilis, 363 Anoplura, 218, 220 colour vision in, 629 eyes of, 221 conus, 363 See, also Pediculus. parietal eye, 715, 718 Anoptichthys jorduni, degenerate eyes in, function of, 719 725 visual field, binocular, 682 Anser, brain, 533 Amelia, visual cells of, 364 Anseriformes, annular jaad, 409 Annelids, 190 infula, 417 dermal sensitivity in, 114 pecten, 412, 414 eyes of, 190 See also Ducks, Cereopsis, etc. light-sense in, 572 Ant, 219 nerve-net, 516 eyeless types, 729 nervous system, 519, 520 homing of, 68 neuro -endocrine system, 550, 552 menotaxis in, 68 See also Polychsetes, Oligochsetes, ocelli, 224 Leeches. time-memory in, 22 Annular ligament, characteristics in vision of, 582, 585 chondrosteans, 317 white. See Termites. holosteans, 321 Ant-eaters, 445 lamprey, 267 banded, 437 teleosteans, 295 vision of, 601 pad, characteristics in giant, 600 birds, 409 spiny. See Echidna. chelonians, 372 Antelope, 446 crocodilians, 377 Anterior chamber angle, characteristics in lacertilians, 360, 361 birds, 404, 405 marsupials, 439 chelonians, 372 782 INDEX

Anterior chamber angle, characteristics in Aphaniptera, 219, 220 chondrosteans, 317, 319 Aphid, 225 coelacanth, 315 eyes of, 224, 225 crocodilians, 376 Aphis forbesi, reproductive cycle in, 17 dipnoans, 313 Aphrophora spumaria larva, ocellus of, holosteans, 321 140 lacertilians, 359 Aphyonus, degenerate eyes of, 724 marsupials, 439 Apis, 58 placentals, 464, 465 colour vision in, 587, 588 selachians, 285 conditioning of, 583, 588 snakes, 386 cornea, transparency of, 584 Sphenodon, 380, 381 luminosity-curve of, 585 teleosts, 303 ommatidial angle of, 172, 173 urodeles, 347 orientation to jDolarized light, 66, 70 pad of lens, in snakes, 389 spectral sensitivity of, 585 Antholoha, phototactic reaction of, 571 telotaxis in, 56, 58 Anthozoa, 182 vision of, 584, 585 See also Sea-anemone, Coelenterates. Aplocheilichthys, iris, PI. II Anthrohia, eyes lacking in, 724 Apoda, 333 Anthropoidea, 443 eyes, rudimentary, of, 730 area centralis, 485 pineal organ, 714 colour vision in, 635 vision of, 599 diurnal, 604 Apodernus. See Mouse, field- fovea, 659 Apposition eye, 169, 173 nocturnal. See Nyctipithecus. Apteryx, 397, 398, 604 optic axis, 688 annular pad, 409 orbit, 498 extinction of, 604 visual field, binocular, 689 eyes of, 401 See also Apes, Primates. fundus, 410, PI. XII Antilocapra. See Pronghorn. pecten, 411, 413, 414 Anurans, 334 refraction of, 639 accomniodation in, 648 Apus (Triops), 76, 208 colour vision in, 627 dorsal light reaction in, 75 eyes of, ZMff., 336, PI. Ill eyes of, 209 I lateral line organs, 534 Aquatic placentals, 502 migration of retinal pigment, 614 choroid, 457 visual cells, 616 keratinization of cornea, 456 ocular movements in, 694 lacrimal passages absent, 494 pineal organ, 714 lens, 474 refraction of, 638 ocular adnexa, 501 vision of, 599 sclera, 450 visual acuity of, 661 shape of eye, -448 field, binocular, 682 sphincter muscle, 468 Seealso Hyla, Rana, Xenopiis, etc. See also Cetaceans, Pinnipedes, etc. Apes, anthropoid, 443 vertebrates, lateral line, 534 ciliary region, 461, 463 Aqueous humour, drainage of, in mam- Harder 's gland, 494 mals, 472 Moll's gland, 492 origin of, in cyclostomes and fishes, pectinate ligament, 464 267 vision of, 602 Arachnids, 211 colour, 635 eyes of, 211 visual field, binocular, 689 compound, 160 See also Primates, Chimpanzee, etc. inverted retinae in, 149 INDEX 783

Arachnids, luminous organs in, 740 A rniad ill id i urn , 4 5 neuro -endocrine system, 552 tropotaxis in, 54 vision of, 579 alteration of resjionse, 45 visual centres, 524 Armadillo, 442, 445 Araneida, 213 cornea, keratinized, 456 eyes of, 213 pineal body absent ,711 nervous system, 521 retina, jjure-rod, 610 vision of, 579, 591 visual cells, 482 Araneus diadematus, 214 Arrow-worms, 194 eyes of, 213 See also Sagitta, Spadella. Area, eyes of, 151, 201 Artemia, 207 light -shadow reflex in, 574 dorsal light reaction in, 75 Archiannelids, 190, 193 Arteria anastomotica in placentals, 498, ocelli of, 193 499, 500 Archicortex, 543 Artery, central retinal, 477 Archistoma, eyes of, 221 Arthrojiods, 204 Arctocebiis. See Agwantibo. blind, 729 Ardea, 404 cerebral ganglion, 521 goliath, binocular vision, 675 activity of, 524 Area centralis, characteristics in function of, 524 anurans, 342 eyes of, 204j^. birds, 417 degenerate, 724, 729 chelonians, 374 luminous organs in, 740, 746 crocodilians, 377 nervous system, 521 lacertilians, 365 neuro -endocrine system, 550, 552 placentals, 485 vision of, 577 selachians, 288, 289 ^ee cdso Insects, Crustaceans, etc. teleosts, 309 Artiodactyla, 445 function of, 657 area centralis, 485 occurrence of, 657 orbit, 497 Arenicola marina, 190 I^upil, 472 diffuse sensitivity of, 191 See also Pig, Deer, etc. eyes lacking in, 729 Ascaris, 187, 190 larva, tropotaxis in, 52 Ascidia, 228 visvial pigment in, 120 larva, 228 Argentea, characteristics in Ascidians. 228 chondrosteans, 317 bioluminescence in, 740 holosteans, 321 eyes of, 228 lamprey, 267 larvse, eyes of, 228 Latimeria, 315 nervous system, 519, 530 selachians, 285 vertebrate eye developed from, 245 teleosts, 296 nervous system, 519, 530 function of, 296 neuro-endocrine systeni, 552 Argyropelecus, 322 Asellus, 207 eyes of, tubular, 323. 324 conditioning of, 579 luminous organs, 741 eyes lacking in, 207, 722 rods, lengthening of, 611 Asio, infra-red rays and, 630 Arhythmic animals, 603 Asplanchna, dermatoptic sensitivity in, 32 eye, characteristics of, 612 Ass {Eqnus asinus), 446 Ariolimax, optic ganglia, activity of, corneal epithelium, 452 524 corpora nigra, 469 Aristelliger, triple cones in, 308, 364 extra-ocular muscles, 495 Aristeomorpha, photopigments in, 121 nictitating membrane, 493 784 INDEX

Ass, Somali wild, 686 Baboon, colour vision in, 635 See also Equidae refraction of, 639 Astacus, 164 Bacteria, luminous, 737, 743 eyes of, 164 Bacterium photometricum, activity of, 34 nervous system, 521 Badger (Meles), 444, 445 Astaxanthin, 120 Balcena. See Whale, right-. absorption spectrum of, 120 Balcenoptera. See Whale, blue. in Euglena, 48 Balanoglossus, 227 Asterias, 185 nerve-net, 515, 530 phototactic reaction of, 571 nervous system, 517, 530 visual organs of, 185 sense organs, 227 Asteroidea, 184 Balanus, 209 See also Starfishes. adult, degenerate eyes in, 722 Astroscopus, 751 larva, eyes of, 209 electric organ of, 751, 752 shadow-reflex in, 45 sclera, 292 Balistes, fovea of, 310 visual field, binocular, 680 Bandicoot, 441 Astur palumbarius, 403 nictitating membrane, 441 ciliary region, 406 pupillary flocculi, 439 scleral ossicles, 403 Barathronus, degenerate eyes, 724 Ateles. See Monkey, spider. Barbatula, colour preference in, 624

Atherina, 617 Bathothaunut , 203 colour preference in, 625 stalked eyes of, 203 threshold to light, difference, 617 Bathygohius, interocular transfer in, 698 Auditory centre, in vertebrates, 534 Bathylagus benedicti, 310, 323 sense, of bats, 601 fovea, 310, 611 dog, 601 visual cells, 305, 611 " " fishes, 598 Bathypterois, feelers in, 724 cave-, 726 Bathyteuthis, eyes of, 146 insects, 581 Bathytroctes, fovea, 310 spatial judgments and, 667 visual cells, 305 Auks, accommodation in, 643 Batoidei, 279 nictitating membrane in, 424 eyes of, 282 Aurelia, 183 See also Selachians, Raja, Torpedo, etc. phototactic reactions of, 571 Bats, 443 aurita, sen.se organs, 183 eyelids, 491 Austrolethops, degenerate eyes in, 726 eyes of, 449 Autochthonous layer of cornea, 295 hearing in, 601 Auxins, 39, 510 lens, 606 isolation of, 41 nictitating membrane, 493 Averna sativa (oat), phototropism in, 40, ocular movements of, 696 119 optic axis, 688 Avicula, 200 refraction of, 639 light-shadow reflex in, 574 retina, pure-rod, 610 sense organs, 200 retinal vascularization, 480 Axolotl, 346 vision of, 601 perception of movement in, 705 visual cells, 482 visual cells, 348 Bdellostoma, eyes of, 263, 734 Bears, 445 B nictitating membrane, 492, 493 optic axis, 688 j8-carotene, 119 polar, pupils, 471 Baboon, 443 pupils, 471 INDEX 785

Bears, retinal vascularization, 479 Birds, ciliary ganglion, 501 sloth-, pupil, 471 colour changes in, control of, 560 retractor bulbi, 495, 496 rhythmic, 21 Beaver, 442, 445 seasonal, 21 diurnality of, 604 vision in, 621, 629 fundus, PI. XV distance, judgment of, 700, 702 optic axis, 688 diurnal, 603 retinal vascularization, 480 eyes of, 400, 401j^., 606 Bees, 219, 220 efficiency of, 256 brain, 524 flightless, extinction of, 604 bumble-. See Bomhus. fovea, function of, 658 colour vision of, 587 fundus. PI. XII compound eye, 166 irides, PI. XI " " dancing of, 70 lateral geniculate body, 541 honey-. See Apis. mid-brain, 535 ocelli of, vision of, 582 migration of, 17, 63 optic centres, 525 of cones, 616 stinging reflex, 526 of retinal pigment, 614 telotaxis in, 56, 58 navigation by, 63 time -memory in, 22 nocturnal, 604 vision of, 585 ocular movements in, 695 visual acuity of, 588, 589 oil-droplets in, 631 Beetles. See Coleoptera. olfactory sense in, 600 fundus, PI. XIII Belideus sciureus, optic lobes, 535 Belone, visual field, binocular, 680 thalamus, 540 of, 724 Bengalichthys, eyes 279, pineal organ, 716 Beyithobatis, eyes of, 279, 723, 724 pupillary reactions, 700 Bergmeister's papilla, 477 refraction of, 639 Beryx, 303 reproductive cycle in, 17 choroidese, 303 tensor control of, 559 Betta, 84 size, judgment of, 703 pugnax, colour changes in, 84 spatial judgments, 702 splendens, colour vision in, 626 summation, retinal, 660 Bibio marci, eye of, 161 tectum, 535 Bifoveate retina, in Anolis, 365, 366 time-memory in, 22 in birds, 418 vision of, 600 Bigeminal body, 534 visual acuity of, 662 Binocular vision, 697 fields, binocular, 681, 683, 684 visual fields, 672 uniocular, 672 Bioluminescence, 736 pathways, 539, 544 extracellular, 745 Bison, 446 intracellular, 746 Bitis arietans, 392 mechanism of, biological, 744 visual cells, 391, 392 chemical, 747 Bittern. See Botaurus. occurrence of, 737 photoperiodism in, 21 Bivalves, 196 purpose of, 741 eyes of. 200 Birds (Aves), 397 degenerate, 722 accommodation in, 651 nervous system, 527 brain, 533 vision of, 574 etc. transection of, 534 See also Molluscs, Avicula, Mya, cerebral cortex, 543 Blatta orientalis, 34 removal of, 545 activity of, 34 50 S.O.—VOL. I. 786 INDEX

Blattella germanica, photo-responses, con- Botaurus, bifoveate retina, 418 ditioning of, 108 binocular vision, 685 phototaxis in, 43, 45, 114 stellaris, 685 Blennius, 310 Bovidje, 446 fovea of, 309, 310 See also Cattle, Sheep, Goat, etc. ocular movements, 693 Box, colour preference, 625 pholis, conditioned reflexes and colour visual field, binocular, 679 vision, 623, 625 Brachiopods, 195 sanguinolentis, accommodation of, 645 larvae of, ocelli in, 195 Blood constituents, diurnal rhythm in, 13, Brachium tecti, 541 15 Bradypus. See Sloth, 3-toed. Blood supply to eye, 482 Brain of vertebrates, 533 characteristics in development of, 531, 532 anurans, 340 See also Cerebral ganglion. birds, 415 Branchellion, 193 crocodilians, 378 ocelli of, 193 lacertilians, 362 Branchiomma vesiculosuni, 192 lamprey, 266 ocelli, 151, 193 marsupials, 439 phototropic movements in, 39 monotremes, 436 Branchionus, dermal sensitivity in, 114 placentals, 477, 498 ocellus, 194 snakes, 390 tropotaxis in, 53 Sphenodon, 381 Branchiopods, 207 teleosts, 299 eyes of, 209 urodeles, 347 See also Daphnia, Apus, etc, vertebrates, 476 Branchiostoma lanceolatum. See Am- Blow-fly, blue-bottle. See Calliphora. phioxus. Boa. See Constrictor, Charina, Epicrates. Brittle-stars, 184 Boar (Sus scrofa), 445 bioluminescence in, 739, 746 Boidte, fundus, 389 Briicke's muscle (ciliary) in birds, 405, hyaloid vessels, 390 406 iris, 387 in lacertilians, 357 lens, 389 in marsupials, 439 optic disc, 390 Bryozoa. See Polyzoa. visual cells, 392 B-substance, in amphibians, 98 field, binocular, 684 Bubo, accommodation in, 651 Boiga dendrophila, iris, 387, PI. IX eyelids, 425 Bolitotherus corriutus, retinal pigment, pecten, 412 migration of, 19 summation, retinal, 660 control of, 556 ascalaphns, 606 Bombinator ignetis, 339 binocular field of, 681 colour changes in, 84 lacteus, 422 vision in, 628 orientalis, iris, 408 pupil of, 339 tensor choroideae, 406 Bombus, 219 Buccinuni, 197 mnemotaxis in, 79 oceUi, 142, 197 vision of, 584 Bufo, 334, 341 Bonihylius, 219 area centralis, 344 colour vision in, 587 colour blindness of, 628 Bombyx, reactions of, 526 fundus, 341 Bony fishes. See Osteichthyes. arenaruni, colour changes in, 97, 558 Book-lice, 218 iris, 337 Borodinula infans, visual field, 679 bufo, iris, 337 INDEX 787

Bufo marinus, fundus, 341 Callionymus, visual cells, 307 iris, 337, PL III Calliphora, 219 viridis, iris, 337 electroretinographic responses, 586 Bugula, 46 ocellus, 140 phototaxis in, 46 optic ganglia, activity of, 524 flabellata larva, ocelli, 195 vision of, 584 turrila larva, ocelli, 195 visual acuity of, 588 Bull. See Cattle. erythrocephala, maggot, 50 Bullfinch. See Pyrrhula. phototaxis in, 47, 50 Burbot. See Lota. vomitoria, telotaxis in, 56 Burrowing habit, degenerate eyes due to, Calotermes flavicollis, lai'vas, phototaxis in, 728 43 Bursalis muscle, in birds, 424 telotaxis in, 56 in lacertilians, 368 Calypte, bifoveate retina, 418 Bush -baby. See Galago. Cambarus, eye-stalk, 523, 553 Bush-cat {Felis libyca), ciliarv processes, nervovis system, 522, 524 466 neuro -endocrine system, 553 Buteo, 417 retinal pigment, migration of, 19 bifoveate retina, 417, 418 ayersii, sensitivity of, 104, 114, 115, summation, retinal, 660 724 visual acuity of, 657 virilis, metabolic rhythm in, 16 Butterflies, 219, 220 photopigments in, 121 aggregate eyes in, 159 Camel (Camehis bactrianus), 446 colour vision in, 587 corpora nigra, 469, 470 neu'.o -secretory cells, 555 eyelids, 491 retinal pigment inigration in, 170 tactile vibrissse, 492 visual acuity of, 588 See also Tylopoda. See also Vanessa, Pieris. Campanula of Haller, in holosteans, 321, 647 in teleosts, 302, 646 Canal of Schlemm, 473 of Sondermann, 473 Cahrita, eyelids, 366 Canida>, 445 Cacatua roseocapella, orbits, 425 ocular movements, 696 Cacicus cela, iris, 407 optic disc, 486 Caddis-fiies, 219. 220 pupil, 471 larvae, ocelli, 222 retinal vascularization, 479 neuro -endocrine system, 555 See also Dog, Fox, etc. CCecilia, eyes, 730 Capra. See Goat. Csecilians, 334 Caprella, 207 pineal organ, 714 Caprimnlgus europceus, 410 retina, pure-rod, 610 fundus, 410, PL XII rudimentary eyes, 730 pecten, 412 Caiman, 375 Capsule, lens, in jDlacentals, 474, 653 iris, PL VIII variation in elasticity, 652 visual field, binocular, 682 Capuchin monkey. See Monkey, Calamokhthys, 278, 320 capuchin. eyes of, 320 Capybara, pupils, 472 retina, pure-cone, 611 Carassius atiratus, 292 Calanus, 207 double cones in, 308 Caligus, 208 iris, PL II eyes of, 209 phototaxis in, 45 Calliactis, nerve trunk, 516 pigment epithelium, 305 788 INDEX

Carassius auratus Cartilage, scleral, characteristics in sclera, 292 chondrosteans, 317 telescope-oyed, 324 crocodilians, 376 iris, PI. II dipnoans, 313 visual cells of, 307 holosteans, 321 Carausius, colour changes, control of, 556 lacertilians, 356 Carcharodon, pupils, 286 Latimeria, 315 Carcinus, colour vision in, 578 monotremes, 433 eyes of, 163 Notoryctes (nodules), 438 metabolic rhythm in, 15 selachians, 281 Cardium, 200 Sphenodon, 380 accommodation in, 591 teleosts, 292 eyes of, 147, 200 urodeles, 347, 349 Carinaria, 199 occurrence of, 450 eyes of, 199 Cartilaginous fishes. See Chondrichthyea, Carinatse, 397 Cassowary. See Casuarius. Carnivores, 445 Castor. See Beaver. accommodation, 653 Casuarius, 397, 406 area centralis, 485 pecten, 311, 413 arhythmic, 604 tensor choroideae, 406 blood supply to eye, 498 Cat (Felis doniestica), 445 ciliary muscle, 462 accommodation in, 653 processes, 467 angle gamma, 676, 677 region, 460, 461, 463 anterior chamber, 465 circle of Hovius, 472 area centralis, 485 colour blindness of, 634 blood svipply to eye, 499, 500 cornea, 453 chiasma, 487 iris pigmentation, 469 colovir blindness of, 634 lateral geniculate body, 489 cornea, 453 Moll's glands, 492 eye of, 449 nictitating membrane, 493 eyebrows, 492 nocturnal, 604 interocular transfer, 698 ocular movements, 696 iris pigmentation, 469 optic axis, 688 lamina cribrosa, 489 disc, 486 MolFs glands, 492 orbit, 497 nictitating membrane, 493 pectinate ligament, 464 occipital cortex, removal of, 546 pupil, 470, 471, 472, 612 olfactory sense in, 601 reactions of, consensual, 700 optic nerve-head, 488 retinal vascularization, 479 pectinate ligament, 464 tapetvim cellulosum, 459, 609 pupils, 470, 471 vision of, 601 contraction of, 612, 613 visual acuity, 663, 664 reactions of, 472 field, binocular, 689 refraction of, 639 zonular fibres, 475 retinal vascularization, 477, 478, 481 Carotenoid pigments, 88, 118 retractor bulbi, 495 absorption spectra of, 119 svimmation, geniculate, 611 Carotid circulation, in placentals, 499 tapetum cellulosum, 457, 458 Carp. See Cyprinus carpio. threshold to light, absolute, 617 Cartilage, scleral, characteristics in vision of, 601 anurans, 334 visual acuity of, 665 birds, 403 field, binocular, 673, 687, 689 chelonians, 369 uniocular, 670, 672 INDEX 789

Caterpillar, 46 Central organization of vision, 509 colour changes in, 92 Centrophorus calceus, pupils, 286 nervous system, 522 Centrostephanus longispinus, 117 ocelli, 222 pigment in, 117 phototaxis in, 46, 114 Cephalaspis, 234 vision of, 582 eyes of, 238 Catfishes. See Siluridae, Ameiurus, etc. pineal organ, 713 Cattle {Bos taurus), 446 Cephalochordata, 228 area centralis, 485 See also Amphioxus. blood supply to eye, 499, 500 Cephalopods, 196 cinary ganglion, 501 accommodation in, 590 colour blindness of, 624, 634 blind, 723 conjunctiva, 491 cerebral ganglion, 528 glands of, 491 chromatophores, 85, 86 cornea, 453 colour changes in, 82, 93, 105 epithelium of, 452 eyes of, 143, 201 lacrimal gland. 493 degenerate, 723 Moll's glands. 492 iris, contraction to light, 89 nictitating membrane, 493 luminovis organs in, 740 optic axis, 688 nervous system, 527 orbit, 498 neuro-secretory cells, 552 pectinate ligament, 464 pupils, 146 pineal organ, 716 contraction of, 89 pupillary reactions, 472 retina, 145 retinal vascularization, 479 vision of, 575 visual field, binocular, 689 See also Octopus, Sepia, Nautilus, etc. uniocular, 672 Cephalopsin, 120 vitreous, 476 Cerambycidae, eyes of, 160 Caudata. See Urodeles. Ceratopogon, eye of, 224 Causus rhombeatus, visual cells, 391 Cercocebus. See Mangabey. Cave-fishes, 725 Cerebral cortex, 543 degenerate eyes in, 725 ablation of, 545 dermal sensitivity, 114 Cerebral (cephalic) ganglion, 518 Cavemicolous habit, degenerate eyes due in arthropods, 521, 522, 525, 526 to, 724 activity of, 524 Cavia. See Guinea-pig. function of, 524 Cavy, Patagonian, diurnality of, 604 removal of, 525 pupil, 472 molluscs, 527 spotted, optic axis, 688 worms, segmented, 519, 520 tapetum fibrosum, 458, 609 unsegmented, 518, 519 See also Guinea-pig. vesicles, 531, 532 CajTnan. See Caiman. Cereopsis, annular pad, 409 Cebidse, 443 pecten, 412

See also Monkey, capuchin ; Xycti- Cervus porcinus, fundus, PI. XIV pithecus, etc. Cestodes, 187 Cebus. See Monkey, capuchin. nervous system, 519 Cells of Hesse, 230 sense organs lacking in, 734 of Joseph, 229 Cetaceans, 446 Centipedes, 210 choroid, 457 eyes of, 210 cilia lacking, 492 See also Myriapods. ciliary receptor organs, 467 Central body, in arthropods, 521 cornea, 453 nervous sytem, 630 keratinized, 456 790 INDEX

Cetaceans, dilatator rimse palpebraruin, Chelodina longicollis, fundus, 372 492 transparent eyelids, 374 eyes of, 449, 451 visual cells, 373 lacrimal passages lacking, 494 Chelonia mydas, conus, 372 secretion, 493 eye of, 354 lens, 474 Chelonians, 353 ocular adnexa, 502 accommodation in, 651, 652 pineal apparatus absent, 711 colour preference, 628 pupil, 472 eyes of, 368j^., 370, PL VII operculum of, 470 ocular movements of, 694 refraction of, 639 pineal organ, 716 retina, pure-rod, 610 refraction of, 639 retractor bulbi, 495 retina, cone -rich, 612 sclera, 450, 451 retinal pigment, migration of, 614 sphincter muscle, 468 threshold to light, difference, 618 summation, retinal, 660 vision of, 599 tapetum fibrosum, 457, 458, 609 visual acuity of, 661 vibratory sense in, 601 field, binocular, 682 vision of, 601 Chelonidse, 369 visual cells, 483 Chelydra serpentina, conus, avascular, in Cetomimus, degenerate eyes, 724 embryo, 372 Cetonia, 219 fundus, 372 colour blindness of, 586, 587 visual cells of, 374 Chsetognaths, 194 field, binocular, 682 eyes of, 152, 194 Chemical sense of crustaceans, 579 See also Sagitta, Spadella. Dytiscus, 103, 104 Chcetopterus, biolumineseence in, 739, fishes, 598 745 Pecten, 103 Chameleon, 355, 695 vertebrates, 597 annular pad, 361 worms, 572 ciliary body, 356 Chemo -receptors, 116 colour changes in, 87 Chemotaxis, 33 control of, 558 Chevrotain {Tragulus), 444, 446 rhythmic, 20 Chiasmal decussation, 487, 697, 698 conus, 363 in birds, 423 eyelids, 366 placentals, 487 eyes of, 605 selachians, 289 fovea, 365, 659 snakes, 392 fundus, 362, PI. VI teleosts, 311 lacrimal gland lacking, 368 Chicken. See Gallus, lens, 360 Chilopoda, 210 ocular movements of, 368, 694 eyes of, 210 scleral cartilage, 356 See also Myriapods. spatial judgments, 701 Chimcera monstrosa, 290 vision of, 599 Chimaeras, eyes of, 290 visual acuity, 657, 661 retina, pure-rod, 610, 611 field, uniocular, 670, 671 threshold to light, absolute, 616 Chanos, lids in, 311 Chimpanzee, 443 Charax, colour preference in, 625 colovir vision in, 635 Charina, ciliary region, 385 cornea, 453 Charybdea, 183 extra-ocular muscles, 495 ocellus of, 138 eye of, 605 Cheetah, 445 interocular transfer, 698 INDEX 791

Chimpanzee, vision of, 602 Chromatoblasts, 117 visual acuity of, 665 Chromatophores, 85 Chinchilla, 445 action of light on, 89 optic axis, 688 control of, 92 pupil, 470, 472 in crustaceans, 94, 554 retina, pure-rod, 610 insects, 93, 555 vascularization of, 480 vertebrates, 95, 558 visual cells, 483 Chromatophorotropins, 93, 554, 555 Chipmunk, pupils, 472 Chrysemys, area centralis, 374 Chironorrnis, nervous system, 522 conus, 372 Chiroptera. See Bats. iris, 370, PI. VII Chiton, 196 Chrysochloris. See Mole, golden. homing ability of, 575 Chrysops marmoratus, visual cell of, 128 photosensitivity of, 197 Chrysotis, green oil-droplets, 420 sense organs of, 196, 723 Cichla, 291 Chktmydosaurus, 3o6 Cicindela, larvae, form vision in, 582 colour changes in, 84 Ciconiiformes, annular pad, 409 Chlorophyll, 5 See also Ardea, Botaiirus, etc. Choanoid muscle. See Retractor bulbi. Cilia, in light-sensitive cells, 128 Choloepus. See Sloth, 2-toed. rhythniic movements of, 511 Chologaster, eyes of, 726 (eyelashes), in mammals, 492 Chondrichthyes, 235, 278 Ciliary canal. See Ciliary cleft, eyes of, 279 cleft, in birds, 405 See also Selachians, Holocephalians. in mammals, 461, 466 Chondrosteans, 235, 278 folds, in selachians, 285 accommodation lacking in, 640 ganglion, in vertebrates, 501 choroidal tapetum, 609 ligament. See Tensor choroideae. eyes of, 315, 318 muscle, characteristics in nocturnality of, 603 amphibians, 335 See also Acipenser, Polypterini birds, 405 Chordates, 227 chelonians, 372 central nervous system, 530 crocodilians, 376 See also Protochordates, Vertebrates. lacertilians, 357 Choroid, characteristics in inarsupials, 438 anurans, 335 I^lacentals, 461 birds, 404 Sphenodon, 380 chondrosteans, 317 teleosts, 302 dipnoans, 313 accommodation and, 650 holosteans, 321 configuration of, 654 lacertilians, 356 occurrence of, 654 lamprey, 266 papilla, in chondrosteans, 317 Latimer ia, 315 in selachians, 284, 285, 647 marsupials, 438 processes, characteristics in placentals, 457 anurans, 336 selachians, 281 birds, 405 snakes, 385 chelonians, 372 Sphenodon, 380 crocodilians, 376 teleosteans, 296 marsupials, 438 urodeles. 347 monotremes, 433 Choroidal gland of holosteans, 321 islacentals, 466 of teleosts. 297, 298 selachians, 284 papillse, in bats, 459 urodeles, 347 Chortippus, optic ganglia, activity of, 524 receptor organs, 467 792 INDEX

Ciliary region, chai'acteristics in Citellus citellus. See Souslik. anurans, 335, 338 Civet cat, 444, 445 birds, 403, 405, 406 Cladocera, 207 chelonians, 361, 372 conditioning of, 578 chondrosteans, 317 orientation to polarized light in, 73 crocodilians, 376 phototactic response of, 578 lacertilians, 356, 358 See also Daphnia, Polyphemus, etc. Latimeria, 315 Cladophora, eye -spot in, 125 marsupials, 438, 439 Clemmys, 682 monotremes, 433, 434 iris, 370 placentals, 460, 461 visual field, binocular, 682 selachians, 283 Clethrionomys. See Vole, red-backed. snakes, 385, 388 Clupea harengus, 299 Sphenodon, 380 falciform process, 299 teleosts, 301 larvae, activity of, 34 urodeles, 347 pilchardus, visual cells of, 307 roll, in snakes, 386, 388 Clupeidae, adipose lids in, 311 sinus. See Ciliary cleft, See also Clupea, Engraulis, Chanos. venous plexus, in placentals, 472, 473 Cnidaria, 182 sinus, characteristics in Coati, 444, 445 anurans, 336 pupils, 472 birds, 408 Cobra, 386 chelonians, 372 See also Elapidae, Naja. crocodilians, 376 Cochlea, 534, 690 lacertilians, 359 Cockle. See Cardium. marsupials, 439 Cockroach, 218, 220 monotremes, 435 nocturnality of, 34 snakes, 386 vision of, 584 Sphenodon, 380 See also Blattella, Blatta, Periplaneta. See also Schlemm's canal, Cod. See Oadus. web, in mo"notremes, 435 Coelacanth, 235, 278, 315 Ciliata, 180 accommodation lacking in, 640 Ciliophora, 180 choroidal tapetum, 609 Cilio-scleral sinvis. See Ciliary cleft, eyes of, 314, 316 Cinyxis erosa, fundus, PI. VII nocturnality of, 603 Ciona, pigmented spots in, 228 retina, rod-rich, 610 Circle of Hovius, 472 Coelenterates, 181 Circulus arteriosus iridis major, 468 bioluminescence in, 739, 745, 748 minor, 468 rhythmic, 22 Circum-ocular sulcus, of teleosts, 311 myo -epithelial cell, 513 Circum- oesophageal ring, in crustaceans, nerve-net, 512, 514, 515 521 phototactic reactions of, 571 insects, 521, 522 sense organs of, 182 molluscs, 527 Colaptes, choroid, 405 Circus movements, 54, 525 auratus, 420 Cirripedes, 208 green oil-droplets, 420 eyes of, 209 Coleonyx, rods of, 364 vestigial, in adults, 209 Coleoptera, 219, 220 nauplius of, 208 eyes of, 167, 224 eyes of, 209 larvae, ocelli of, 141, 223 nervous system, 521 luminous organs in, 740, 742, 748 Cirrothauma murrayi, eyes lacking in, 723 neuro-endocrine system, 555 Cistella, larva, ocelli in, 195 See also Dytiscus, Necrophorus, etc. INDEX 793

Collembola, 217,- 218 Columba luminous organs in, 740 visual acuity of, 662, 665 ocelli, 159, 221 field, binocular, 682, 684 Colliculi, inferior, 534 uniocular, 672 superior, 534 livia, iris, 408 Colcelus monedula, iris, PI. XI See also Homing pigeon. Colour changes, 82 palumbus, pecten, 413 colour vision and, 621, 625 Columbidae, eyes of, 402 control of, 92 See also Columba, Streptopelia, etc. in crustaceans, 554 Comb-jelly, 182 insects, 555 bioluminescence in, 739 vertebrates, 558 sense organs of, 182 demonstrative, 83 Compound eyes, 153 mechanism of, 85 composite, 160, 591 protective, 82 of crustaceans, 160 rhythmic, 19 of insects, 1 60 preference, 623 development of, 156 vision, in cephalopods, 575 optical system of, 170 crustaceans, 578 structure of, 155, 157 insects, 586 of arachnids, 160 spiders, 580 crustaceans, 163 vertebrates, 619 insects, 166 in amphibians, 627 Compressor lentis, in birds, 651 birds, 629 Conditioned reflexes, 568 cyclostomes, 624 colour vision and, 623 fishes, 624 Cone, crystalline, 157 mammals, 632 Cones (vertebrate), 250 reptiles, 628 differentiation from rods, 251 investigation of, 620 double, 253 methods of testing, 621 in anurans, 342, 344 Coluber guttatus, fundus, 389 birds, 419 iris, 386 chelonians, 374 visual field, binocular, 684 holosteans, 321, 322 Colubrids, retina, pure-cone, 611 lacertilians, 364 visual cells, 391, 392 marsupials, 440, 441 field, binocular, 684 platypus, 436 Columba, 64 Protopterus, 313, 314 colour vision in, 630 snakes, 391, 392 conditioning in, 663 teleosts, 307, 308 decerebrate, reactions of, 545 urodeles, 348 eye of, 605 quadruple, 253 hue discrimination in, 619 in teleosts, 308 interocvilar transfer, 698 triple, 253 iris, 407, 408, PL XI in anurans, 342, 344 lens, 409 lacertilians, 364 ocular movements in, 692 teleosts, 308 pecten, 414 twin, 253 pineal organ, 716 in teleosts, 307, 308 pupillary reactions, consensual, 700 Coney. See Hyrax. Purkinje phenomenon in, 629 Conjunctiva, in mammals, 491 retina, 417 Conjunctival bone, in sturgeon, 317 threshold to light, difference, 618 Conolophus subcristatus, conus, 363 transversalis muscle, 407 fundus, 361, 362, PI. VI 794 INDEX

Consciousness, emergence of, 108 Corycceus, 209 Constrictor, ciliary region, 385 Cottus, cornea of, 295 venovis sinus, 386 bubalis, eye of, 302 visual field, binocular, 684 Cow. See Cattle. Contractile pupils, occurrence of, 612 Coypu, 445 Conus papillaris, in crocodiles, 378 optic axis, 688 lacertilians, 362 pvipils, 472 avascular, in embryo turtles, 372 Crabs, 206 vestigial, in marsupials, 440 eyes of, 206 Coot. See Fulica. nervous system of, 521 Copepods, 207 sexual cycle, control of, 555 eyes of, 209 See also Decapods, Carcinus, etc. luminous organs in, 740, 746 Crago (Crangon) vulgaris, 205 Copilia, 209 colour changes in, 94 accoininodation in, 591 vision in, 578 eyes of, 159, 160, 209 eyes of, 165, 206 vision of, 578 ommochroines in, 123 Copperhead snake, 387 Crampton's muscle, in birds, 405, posterior segment of eye, 387 406 Cordylosaurus, transparent eyelids of, in lacertilians, 357 366 Crane. See Orus. Corephium., sense organs of, 196 Crane-flies, eyes of, 167 Cornea, characteristics in Crayfish, 206 amphibians, 334 eyes of, 164, 206 Anableps, 324 sexual cycle, control of, 555 birds, 404 See also Crustaceans, Astacus, etc. chelonians, 369 Crenilabrus, colour changes and colour chondrosteans, 317 vision, 625 coelacanths, 315 rostratus, dorsal light reaction, 76 crocodilians, 376 Crepuscular animals, 602 dipnoans, 312 Cribriform ligament, 461 fishes, 276 Cribrina, phototactic reaction of, 571 holosteans, 321 Crinoidea, 184 lacertilians, 356 Crocodile tears, 379 lamprey, 265 Crocodilians, 353, 375 marsupials, 438 accommodation in, 651, 654

monotremes, 433 eyes of, 376 ff., PL VIII placentals, 452, 453 ocular movements of, 694 selachians, 281 pineal organ, 716 snakes, 385 pupils, contractile, 612 teleosts, 294 Purkinje shift in, 628 yellow, occurrence of, 656 refraction of, 639 Corneal facet, 157 retinal pigment, migration of, 614 nerves in mammals, 454, 455 tapetum, 608 Cornealis muscle, in lamprey, 271 vision of, 599 and accommodation, 645 visual acuity of, 661 Corpora nigra, 469, 612 field, binocular, 682 Corpvis allatum in insects, 555 Crocodilus, 378 cardiacum in insects, 555 porosus, lacrimal glands, 379 Corvidae, eyes of, 402 sclerops, eye of, 354 See also Corvus. Crossopterygii, 234, 235 Corvus monedula, iris, 408 central nervous system, 532 visual acuity of, 663 See also Dipnoans. INDEX 795

Crotalidse, facial pit, 599, 600 Cyclosa rnsulana, camouflage, 83 visual cells, 391, 392 Cyclostomes, 259 Crotalus, olfactory sense in, 599 accominodation in, 644 See also Crotalidae. brain, 533 Crotaphytus, cones, 364 transection of, 534 Crustaceans, 206 central nervous system, 532 blind, 722, 724, 734 colour changes in, 95 cerebral ganglion, 521 control of, 558 removal of, 525 rhythmic, 20 colour changes in, 82, 91, 94 vision in, 624 control of, 554 dermal sensitivity in, 114 rhythmic, 20 diurnal ity of, 603 compound eyes of, 163, 206 eyes of, 259 conditioning of, 579 degenerate, 734 deep-sea. Deep-sea Crustaceans. See fore-brain, 543 eyes of, 206 removal of, 545 725 degenerate, 722, 723, labyrinths, 534 eye-stalk, 523 lateral genicvilate body, 541 neuro -secretory cells in, 551, 553 mid-brain, 535 luminous organs in, 740, 744, 745, 748 ocular movements of, 691 in, 15 metabolic rhythms optic thalamus, 539 control of, 555 palaeocortex, 543 system, nervous 521 jmrietal eye, 713, 716, 717 neuro -endocrine system, 552, 553 pineal eye, 713, 716, 717 in, 123 omjnochromes refraction of, 638 retinal jDigment migration in, 165 secretory inechanism of, 267 control of, 554 tectum, 534 rhythmic, 19 telencephalon, 543 spectral sensitivity of, 585 vision of, 598 time-memory in, 22 visual field, binocular, 678 vision of, 578 pathways, 535, 543 visual centres, 524 pigments in, 121 pigments in, 121 Cymonomus, degenerate eyes of, 723 Cryptobranchus, eyes of, 349 Cynictis, diurnality of, 604 Crypfotympana, ocelli, vision of, 582 pupil, 472 Crystalline cone, 157 tapetum lacking, 459, 609 lens. See Lens. Ctenophora, 182 Cynomys. See Prairie-dog. luminescent, 739 Cypridina, 207 Cuckoo, migration of, 18 bioluminescence in, 746 Culex, scototaxis in, 60 composite ocellus of, 152 Cupulate eyes, 137 Cyprinidse, 291 Cuttlefish, 85, 196 cornea, 294 colour changes in, 85, 93 retinal tapetum, 305, 612 eyes of, 143, 201 See also Cyprinus, Carassius, Phoxi- See also Sepia. nus. Cyanocitta, 414 Cyprinus carpio, 291 pecten, 413, 414 colour vision in, 625 Cyanopsin, 122 cornea, 294, 295 Cybernetics, 106 falciform process, 299 Cyclodorippe, degenerate eyes of, 723 iris, 303 Cyclops, 152 ocular movements, 693 composite ocellus of, 152, 208 visual field, binocular, 679 796 INDEX

Cypris (Cypria), 152, 208 Deep-sea molluscs, eyes of, stalked, 203 composite ocellus of, 152 tubular, 203 Cystoflagellates, 180 luminous organs in, 740, 742 Deer, 446 cornea, 453 D eyelids, movements of, 491 Harder's gland absent, 494 Dacelo gigas, pecten, 413 nictitating membrane, 493 Dafila acuta, visual acuity, 663 optic axis, 688 " Dancing " of bees, 70 visual acuity of, 664 Daphnia, 74, 208 Degenerate eyes, 721 composite ocellus of, 152, 209 Deiters' nucleus, 534 compound eye of, 163, 209 Delphinus. See Dolphin. conditioning of, 578 Demodex folliculorum, 216 dermatoptic sensitivity in, 32, 114, 578 Dendroccelum, 188 dorsal light reaction in, 74 klinokinesis in, 36, 37 Darwin, Charles, 2, 3 ocelli of, 136, 188 Dasychone, ocelli of, 192 Dendrocopus major, 414 Dasypeltis, 392 pecten, 414 visual cells, 392 Dendrocygna, iris, 407, 408, PI. XI Dasypodida?, 445 Dentalium, 197 Dasypus. See Armadillo. eyes lacking in, 729 Dasyure, 437, 438 statocysts of, 197 ciliary muscles, 439 Depressor corneae. See Crampton's pupils, 439, 612 muscle, tapetum fibrosum, 438, 609 palpebrse inferioris, in elephant, 492 visvial cells, 440 Depth perception, 667 Dasyuridse, 437 Dermaptera, 218, 220 See also Dasyure, Tasmanian devil, etc. See also Forficula. Decapods, 206 Dermatopsia, 114 eyes of, 206 Dermatoptic sensitivity, 32, 113 nervous system, 521, 524 of echinoderms, 184 Decussation. See Chiasmal decussation. of rotifers, 194 Deep-sea crustaceans, eyes of, degenerate, Derniochelys coriacea, 369 207, 723 scleral cartilage, 370 enlarged, 207 Dermoptera, 443 luminous organs in, 740, 742 Descartes, Rene, 710, 712 fishes, eyes of, degenerate, 292, 723 Desman, 441, 443 enlarged, 273, 281, 292, 323, 606, Desmid, 35 723 response to light, 35 stalked, 327 Desmodus. See Vampire bat. tubular, 277, 322, 606 Deuterocerebrum, in arthropods, 521 optics of, 642, 643 Diadema antillarum, 185 luminous organs in, 741, 746 colour changes in, 89, 90 pupils, 286 rhythmic, 20 refraction of, 638 dermal sensitivity in, 114, 185 retina, pure-rod, 310, 610 iridophores in, 184 tapetum, retinal, 608 phototropic movements in, 39 threshold to light, 674 setosum, iridophores in, 185 visual acviity of, 657 Dia-heliotropism, 38 I cells, 305, 643 Dialommus fuscus, double cornea, 325 field, vmiocular, 670 Diatom, 35 molluscs, eyes of, degenerate, 723 colour changes in, 82, 89

I INDEX 797

Diatom, response to light, 35 Diurnal animals, 602 Dictyostelium discoideum (slime-mould), eye, characteristics of, 611 thermal stimulation in, 36 retina of, 610, 611 Didelphyidte, 437 rhythins. See Photoperiodism. Didelphys. See Oposum, Virginian. Dixippus, 218 Diencephalon, 532, 537 colour blindness of, 587 photosensitivity in, 537 changes in, 88, 93 pineal apparatus and, 711 control of, 556 secretory activity, 537 rhythmic, 20 Dilatator pupillse, characteristics in metabolic rhythm in, 15 anurans, 337 Dodo, 604 birds, 407 extinction of, 604 lacertilians, 357 Dog {Canis familiaris), 445 placentals, 468 accommodation in, 653 selachians, 285 angle gamma in, 677 snakes, 388 area centralis, 485 Sphenodon, 381 blood supply to eye, 498, 499 teleosteans, 303 cerebral cortex, 543 rimae palpebrarum, in cetaceans, 492 removal of, 545 Dineutus, eyes of, 160 chiasma, 487 choroid, assimilis, circus movements in, 54 shunt apparatus, 460 ciliary region, grosstis, 224 461, 463 circle of Hovivis, 472 Dinoflagellates, 179, 180 colour blindness of, 634 bioluininescence in, 738 conditioned reflexes and, 623 rhythmic, 22 conjunctiva, 491 eye -spot of, 126 cornea, 453 Dinophilus, ocelli of. 193 epithelium of, 452 Dinosaurs, 234, 236 extra-ocular muscles, 496 Dioniedea caiita, 418 Harder 's gland, 494 fundus, PI. XII hearing of, 601 infula and fovea, 418, 420 lacrimal passages, 494 Diplopoda. 210 lens, 474 Dipnoans, 235, 278 Moll's glands, 492 accommodation lacking, 640 movement, perception of, 705, 706 central nervous system, 532 nictitating membrane, 493 eyes of, 312, 313 occipital cortex, removal of, 546 nocturnality of, 603 olfactory sense in, 601 pineal body, 714 optic axis, 688 Diptera, 220 219, pectinate ligament, 464 accominodation, static, in, 591 pigment epithelium, 459, 608 eyes of, 160, 222, 223 pupils, 471 luminous organs in, 740 reactions of, 472 nervous system, 521, 522 refraction of, 639 neuro -endocrine system, 555 retinal vascularization, 477, 478 See also Drosophila, Sarcophaga, retractor bulbi. 495, 496 Musca, etc. tapetum cellulosum, 457, 459 Directional eye, 132, 135 threshold to light, difference, 618 Discrimination box, 569 visual acuity of, 664 Dispholidus, visual field, binocular, 684 field, binocular, 689 Distance, perception of, in insects. 589 Dogfishes, 279 in vertebrates, 701 eyes of, 282 receptors, 116 See also Mustelus, Squalus, etc. 1

798 INDEX

Dolichopteryx, tubular eyes in, 324 Dytiscus inarginalis Dolphin, 444, 446 larva, dermal sensitivity in, 114 cornea, 453 ocelli of, 221 keratinized, 456 optic ganglion, activity of, 524 ocular adnexa, 502 sensory reactions of, 103, 588 pineal body absent, 71 vision of, 584 Dormouse, choroid, 457 pupils, contractile, 612 E retinal vascularization, 482 visual cells, 483 Eagle, accommodation in, 651 Dorsal light reaction, 74 bald. See Haliaetus. Dorylus, 221 bifoveate retina, 417, 418 eyes lacking in, 729 Chilean. See Geranoaetus. Dragon-fly, 74 visual field, binocular, 684 compound eyes of, 172, 222 Earthworm, 190 See also Anax, Aeschna. bioluminescence in, 745 Drainage channels in mammals, 472, eyes of, 190 473 tropotaxis, 53 Drepanophorus, ocellus of, 134 visual cells, 131 Driver ant, 221, 729 See also Lumbricus. eyes lacking in, 729 Eccentric cell in compound eyes, 158 Droniceus, 397 Echidna, 430, 431 Dromedary (Canielus dromedarius), 446 ciliary processes, 433 See also Tylopoda. body, 434 Drosophila, 44 eye of, 432 colour vision of, 587 fundus, PI. XIII dermal sensitivity in, 114 optic axis, 688 electroretinographic responses, 586 retina, 435 ommochroines in, 123 pure-rod, 610 optomotor reaction in, 583 scleral cartilage, 433 phototaxis in, 44, 45 Echinoderms, 183 spectral sensitivity of, 585 colour changes in, 82, 90 telotaxis in, 56 rhythmic, 20 time-memory in, 22 dermal sensitivity, 114 vision of ocelli of, 582 luminescent, 739 visual acuity of, 588 nerve-net, 515 Dryophiops, pupils, 388 nervous system, 516 Dryophis, fovea, 388, 392 origin of vertebrates through, 233 pupils, 388, 674 phototactic reactions of, 571 visual field, binocular, 682 sense organs of, 184 Ducks, diving, accommodation in, 643 Echinoidea, 184 ciliary muscles, 407 Edentates, 445 nictitating membrane, 424 nictitating membrane, 493 gonadotrophic activities of, 18 ocular movements of, 696 nervous control of, 537, 560 optic axis, 688 visual fields of, 685 refraction of, 639 See also Dafila, Dendrocygna, etc. vision of, 601 Dugong, 446 Eels, retina, 299, 301 pineal organ absent, 711 snipe-. See Borodinula. retinal vascularization, 480 visual cells of, 307 Dytiscus marginalis, 168 See also Anguilla. brain, 524 Eiseniafmtida, conditioning of, 573 eyes of, 168, 172 tropotaxis in, 53 INDEX 799

Elaphe quadrivitatta, iris, 387, PI. IX ! Ephemeroptera, eyes of, 160 quatorlineata, iris, 387, PI. IX Ephestia, larva, tropotaxis in, 52, 53 Elapidfe, iris, 386 Epicrates, lens, 389 visual cells, 392 Epinephelus, 92 Elaps, pupil, 388 colour changes in, 92 Elasniobranchs. See Chondrichthyes. Epiphysis. See Pineal organ. Elaterid beetles, bioluininescence in, 736, Epomophorus, choroidal papilla?, 459 740 Eptatretus, degenerate eyes in, 734 Electric organs in fishes, 751 Equidse, 446 Electrophorus, electric organ of, 751 ciliary ganglion, 501 Electroretinograi^hic responses, and cornea, 453 colour vision, 622 corpora nigra, 469 Eledone, 146 optic disc, 486 eye of, 146 pupil, 472 Elephants, 446 See also Horse, Ass, Zebra. African, 446 Erax rufibarbis, telotaxis in, 56 cilia lacking in, 492 Ereniias, transparent eyelids of, 366, eyelids, movements of, 491, 492 367 eyes of, 450 Ericymba, visual cells of, 305 immobility of, 497, 696 Erinaceus. See Hedgehog. Indian, 446 Eristalis, telotaxis in, 56 ciliary processes, 466 tropotaxis in, 55 eye of, 447 Erithacus, visual acuity of, 663 lacrimal passages lacking in, 494 visual responses of, 664 optic axis, 688 Ermine, colour changes in, 21 orbit, 497 pupil, 472 retinal vascularization, 480 Errantia, 190 sclera, 450 Erythrominatin, 123 tapetum fibrosum, 458, 609 Erythrophores, 88 visual fields, 689 Eryx, ciliary venous sinus, 386 Zeis's glands, 491 Esocidse, cornea of, 294 Elephas maximus. See Elephant, Indian. Esox lucius, cornea of, 295 Eliomys. See Dormouse. eye of, 275 Ellobius, degenerate eyes of, 733 visual field, binocular, 679 Elysia viridis, menotaxis in, 61 Etmopterus, eyes of, 281 Embioptera, 220 pupil, 286 Ernplectonema kandai, bi(jluininescence threshold to light, absolute, 616 in, 739, 746 visual cells, 288, 290, 611 Emu. See Dromceus. Eucalia, threshold to light, difference, 617 Emyda, fovea, 374 Eucone eye, 167 transparent eyelid, 374 Eudendrium hydroid, phototropic granosa, fundus, 372, PI. VII movements of, 39 Emys, scleral ossicles, 369 jjigment in, 120 orbicidaris, area centralis, 374 Eudyptes cristatus, 40S iris. PI. VII iris, 408, PI. XI

Enchelioph is Jordan i, 735 Euglena, 179, 180 eyes of, 735 gracilis, eye-spot, 126 pupils, 304, 612 virilis, eye-spot, 126 sclera, 292 klinotaxis in, 45, 48, 49 Engraulis, lids in, 311 pigment in, 120 Entosphenus, visual cells of, 269 inigration of, 85, 89 Ephemeroptera, 218, 220 spectral sensitivity of, 120 accommodation, static, in, 591 Eunice, ocelli of, 191 800 INDEX

Eupagurus, 58 Eyes, characteristics in orientation to polarized light in, 73 anurans, 334 telotaxis in, 56, 58 urodeles, 346 Euphagus cyanocephalus, iris, 408 birds, 397 Euphausiopsin, 121 cyclostomes, 259 Eupolyodontes, ocelli of, 192 ammocoete larva, 261 Euproctis, larva, phototaxis in, 46 lamprey, 263 Eurypterids, 157 fishes, 273 eyes of, 157 chondrosteans, 315 origin of vertebrates through, 233 coelacanths, 314 Euselachii, 279 dipnoans, 312 eyes of, 282 holocephalians, 290 Eutheria. See Placentals. holosteans, 321 Evarcha blancardi, 580 selachians, 279 vision of, 580 teleosts, 291 Evermanella, tapetum, non-occlusible, 305, mammals, 429 608 marsupials, 438 tubular eyes in, 324 monotremes, 431 Exocone eye, 168 placentals, 446 Extra-ocular muscles. See Muscles. reptiles, 353 Eyebrows, in mammals, 492 chelonians, 368 Eyelids, characteristics in crocodilians, 375 anurans, 344 lacertilians, 355 birds, 423 snakes, 383 chelonians, 374 Sphenodon, 379 crocodilians, 378 amphibious, in fishes, 324 lacertilians, 366 in insects, 224, 225 monotremes, 436 cerebral, of rotifers, 194 placentals, 491 of vertebrates, 237 selachians, 289 compound, 153 snakes. 392 acone, 167 teleosteans, 311 apposition, 169, 173 urodeles, 349 composite, 160 movements of, in vertebrates, 491 eucone, 167 third. See Nictitating membrane. exocone, 168 Eyes, characteristics in fast, 584, 706 invertebrates, 125 pseudocone, 167 arachnids, 160, 211 slow, 584, 706 brachiopods, 195 superposition, 169, 174 chsetognaths, 194 degenerate, 721 ccelenterates, 182 emergence of vertebrate, 242 crustaceans, 163, 206 evolution of vertebrate, 233 echinoderms, 185 median, 711 insects, 166, 220 migratory, in fishes, 328 molluscs, 196 ontogeny of vertebrate, 239 myriapods, 210 parietal, 713 Peripatus, 204 phylogeny of vertebrate, 237 polyzoa, 194 pineal, 713 rotifers, 194 rudimentary, 721 worms, 188, 190 simple, 129 protochordates, 227 aggregate, 151 vertebrates, 248 composite, 152 amphibians, 333 cupulate, 137 INDEX 801

Eyes, simple, directional, 132 Felidse, spatial judgments in, 704 flat, 136 ^ee also Cat, Lion, Tiger, etc. multicellular, 132 Ferret, 445 ommatidial, 159 moulting cycle of, 21, 560 pallial, 201 pupils, 472 subepithelial, 132 reproductive cycle of, 18 unicellular, 130 control of, 559 vesicular, 141 Fibrils, intercellular, in protozoa, 511, 512 stalked, in fishes, 326 Fiddler-crab. See Gelasimus, Uca. in insects, 223, 225 Fighting fish. See Betta. in molluscs, 203 Filters, intra-ocular, 656 telescopic. See tubular, Fire-flies, eyes of, 168 tubular, in fishes, 322 luminous organs, 740, 742 in molluscs, 203 See also Lampyris, Photinus. Eye-shine, 608 Fishes, 278 Eye-spot, 125 accommodation in, 645, 647 of Euglena, 126 angle gamma of, 677 Marthasterias, PI. I blinded, behaviour of, 598 Pouchetia, 126 brain, 533 Eye-stalk, of crustaceans, 522, 523 transection of, 534 neuro-secretory cells in, 551 cave-, 725 central nervous system, 532 chemo -receptors, 598 ciliary ganglion, 501 colour changes in, 82, 91 Fabricia, ocelli of, 191 control of, 95, 537, 558 Facet, corneal, 157 vision of, 624 Faceted eye. See Compound ej'es. optoinotor reaction and, 623 Facial pit of vipers, 117, 599, 600 respiration rate and, 623 Falciform process, of holosteans, 321 deep-sea. See Deep-sea fishes, of teleosteans, 298, 299 distance, judgment of, 701 Falco, eye of, 399 electric organs in, 751

binocular vision of, 684 eyes of, 273 j5^. subbuteo, iris, 408 amphibious, 324 tinnunculus, ciliary venous sinus, 408 degenerate, 723, 725, 734 fundus, 410, PI. XII median, 713 pecten, 413 migratory, 328 Falconiformes, bifoveate retina, 417 stalked, 326 shape of eyes, 402 tubular, 322 See also Eagles, Hawks, etc. fore-brain, 543 Fasciola hepatica, 187, 189 removal of, 545 larva, ocelli of, 189 hearing of, 598 Fast eyes, in insects, 584, 706 interocular transfer in, 698 visual acuity of, 588 iris, contraction to light, 89 Feather-stars, 184 lateral geniculate body, 541 Feeding responses, 104 line organs, 534, 598 Felidae, 445 luminous bacteria in, 737 area centralis, 485 organs of, 737, 741, 743, 746 eye-shine, 608 median eye, 713 ocular movements in, 696 inid-brain, 535 optic axis, 688 movement, perception of, 706 pupils, 470 neuro-endocrine system, 557 retinal vascularization, 479 neuro-secretory cells, 551

S.O. —VOL. I. 61 802 INDEX

Fishes, ocular movements of, 691, 692 Flying fox, retina, corrugated, 642 voluntary, 693 tapetum in, 459 optic lobes, 534 lemur, 442, 443 thalamus, 540 phalanger, 437 pupillary reactions, 89, 700 retinal circulation, 440 refraction of, 638 tapetum fibrosuin, 438, 609 reproductive cycle in, 17 squirrel, 445 control of, 559 fundus, PI. XV size, judgment of, 701 optic disc, 486 spatial orientation, 701, 702 retinal vascularization, 482 tactile sense of, 598 tapetum fibrosum, 458, 609 tapetvim, occlusible, 612 visual cells, 483 tectvnn, 534 Fontana's spaces (canals), 464 telencephalon, 543 Foraminifera, 179, 180 vibra.tory receptors in, 534, 598 Fore-brain, 532 vision of, 598, 599 See also Diencephalon, Telencephalon, visual acuity of, 660 Forficula, 218 fields, aerial, 672 ommatidial angle in, 172 binocular, 678, 679 phototaxis in, 46 uniocular, 670, 671, 672 scototaxis in, 60 pathways, 536, 543 Form vision, in arthropods, 578 piginents, 121 cephalopods, 576 See also Selachians, Teleosteans, etc. insects, 588 Fissipedia, 445 spiders, 580 See also Felida?, Canidse, etc. vertebrates, 637 Fitzroya lineata, colour changes in, 105 See also Visual acuity. Flagellata, 180 Fossorial habit, degenerate eyes due to, metabolism of, 510 728 phototaxis in, 48 Fovea, characteristics in See also Euglena, Volvox, etc. birds, 417, 420, 421 Flat eyes, 136 lacertilians, 365 Flat-fishes, 328 placentals, 486 colour changes in, 92 snakes, 392 colour vision and, 625 Sphenodon, 382 migratory eyes in, 328 teleosts, 309 twin cones in, 308 turtles, 374 visual field, binocular, 679 function of, 658 See also Soleidse, Pleuronectes, etc. occurrence of, 659 Flat-worms, 187 pure-cone, in birds, 422 See also Planarians, etc. in priinates, 486 Fleas. See Aphaniptera. pure-rod in geckos, 365 Flicker, threshold of, in insects, 584, 589 noctvirnal 23rimates, 486 Flies. See Diptera. Sphenodon, 382 FloccLili, pupillary, in marsupials, 439 teleosts, 310 in placentals, 469 shape of, 659 Floral initiation, 10 Foveolse opticae, 239, 240 Florigens, 549 Fox (Vulpes), 445 Flounders. See Pleuronectes, Para- cornea, 453 lichthys, Psettodes. flying. See Flying fox. Fluorescence, 747 optic axis, 688 Flying fox, 442, 443, 607 disc, 486 choroidal papilla?, 459 pupils, 471 fundus, PI. XV Franz, Victor Julius, 273, 274 INDEX 803 von Frisch, Karl, 566, 567 Galago, visual cells, 482 Frogs, 334 See also Lemuroids. colour changes in, 97 Galeopithecus. See Flying lemnr. control of, 558 Oaleorhinus, eyelids, 289 rhythmic, 20 pupil, 286

eyes of, 334 j^. Galliformes, shape of eye, 402 iris pigmentation, 337 See also Gallus, etc. control of, 558 Gallus domesticus, ciliary region, 403 retinal pigment, migration of, 614 colour vision in, 630, 631 control of, 559 Crampton's muscle, 406 See also Anurans, Hyla, Bana, etc. eye of, 400 Fulica, visual acuity, 663 oil-droi^lets, green, 420 Fulmar us glacialis, retina, 417 pecten, 414 Fundulus, 308 posterior segment of eye, 404 area centralis, 309 retina, 417 colour changes in, 89, 91, 97 size, judgment of, 703 double cones, 307, 308 summation, retinal, 660 migration of rods and cones in, 616 visual acuity of, 663 Fundus, characteristics in Galvanotropism, 33 anurans, 341, PI. Ill Gamma angle. tS'ee Angle gamma. birds, 410, PI. XII Gammarus, blind species, 722 chelonians, 372, PL VII pulex, oiumochronies in, 123 crocodilians, 378, PI. VIII Ganglion, cerebral. See Cerebral lacertilians, 361, PI. VI ganglion. marsupials, 439, PI. XIII Ganglionic nervous system, 517 monotremes. 436, PL XIII in arthropods, 521 placentals, 478. 479, PL XIV, XV molluscs, 527 snakes, 389, PL X worms, 518 Sphenodon, 382, PL VIII Garrulus, pecten, 412 teleosteans, 306 Gasterosteus aculeatus, 84 urodeles, 347, PL IV colour changes in, 84 See also Retina. hue discrimination, 619 Fungi, Iviminous, 737, 743 visual responses, 627, 665 Fungus-gnat larva\ luminous organs in, Gastropacha rubi, eye of. 159 740 Gastropods, 196 Fusion frequency, in fishes, 626 eyes of, 197 in insects, 589 nervous system, 527 vision of, 574 Gavia, accommodation in, 643 G nictitating membrane, 424 Gavial, 375 Gadfly. See Ancala, Tabanus. Gazelle (Gazella), 444, 446 Gadus morrhua, 299 corpora nigra, 469, 470 annular ligament, 295 Geckos, 355, 356 eye of, 275 annular pad, 361 falciform process, 299 ciliary body, 356 fundus, 306 cornea, 356 twin cones, 308 diurnal, eye of, 605 Galago, 443 pupils, 359 fundus, PL XIV visual cells, 364 pupils, 472 fovea, 365 shape of eye, 448 fundus, 361 tapetum cellulosum, 459 iris, 358 804 INDEX

Geckos, lacrimal gland absent, 368 Glow-worm, 740, 742 nocturnal, accommodation in, 651 Goat (Capra), 446 conus, 363 area centralis, 485 eye of, 605 blood supply to eye, 500 fovea absent, 365 conjunctival glands, 491 pupils, 359 corpora nigra, 469, 470 retina, pure -rod, 364, 610 nictitating membrane, 493 rods, thickening of, 611 visual field, binocular, 689 ocular movements in, 694 wild, corpora nigra, 470 pineal organ, 716 Goat -sucker. See Caprimulgus. pupils, 359 Gobiidae, degenerate eyes in, 726 secondary " spectacle ", 366 See also Gobius, Periophthalmus, Typh- visual cells, 364, 643 logobius, etc. See also Gekko, Hemidactylus, etc. Gobius, 296 Oekko gekko, visual pigments in, 122, 252 membrana vasculosa, 299 Qelasimus arcuatus, 205 niger, cornea, 296 Geniculate body, lateral, 541 poecilichthys, membrana vasculosa, 300 functions of, 542 Goldfish, degeneration of eyes in, 722 in mammals, 489, 490, 536 telescope-eyed, 324 in vertebrates, 541 threshold to light, difference, 617 Qeonemertes, ocelli of, 190 visual acuity, 660 Oeoplana mexicana, 188 See also Carassius. ocelli of, 188 Gonadotrophic activities, diencephalon Geotria australis, 260 and, 537 visual cells of, 269 hormonal control of, 550 Geotropism, 33, 667 in crustaceans, 555 Oeotrupes, 61 insects, 556 colour vision of, 586 vertebrates, 559 menotaxis in, 61 photoperiodism in, 16 Geranoaetus, 398 Gonatodes fuscus, pure-cone retina of, binocular field, 681 365 I Gerrhosaurus grandis, iris, PI. V Gonepteryx rhamni, colour vision of, 586 Gibbon, 443 Gonium, eye-spot in, 125

fovea, 486 Gonodactylus , 60 See also Apes, anthropoid; Primates. phototaxis in, 43 Gigantactis, luminous organ of, 745, 746 scototaxis in, 60 Giganturus chuni, 323 Goose. See Anser, Cereopsis. tubular eyes of, 323 Gorilla, 443 visual field, binocular, 680 binocular vision, 687 Gillichthys mirahilis, visual pigments in, cornea, 453 122 fovea, 486 Ginglymostoma, pupil of, 286 iris vascularization, 468 Giraffe {Giraffa), 444, 446 Goshawk. See Astur. angle gamma in, 677 Grasshoppers, 218 optic axis, 688 accommodation in, 591 panoramic field, 686 colour changes in, 94 Girella, fovea of, 310 vision of, 584 Glandula pinealis, 711 See also Acrida. Glaucoma, diencephalon and, 560 Gregarian inertia, 73 photoglycsemic reflex and, 560 Grouse, 402 Glis. See Dormouse. shape of eye, 402 Glossina, 45 Growth, control of, 555, 556, 560 phototaxis in, 45 hormones in plants. See Auxins. .

INDEX 805

Grua, iris, 408 Harder's gland, 345, 494 ocular movements, 696 characteristics in Guanine, 89, 608 anurans, 345 in integument, 89 birds, 425 invertebrate eyes. See. Tapetum. chelonians, 375 vertebrate eyes. See Argentea, crocodilians, 378 Tapetum. lacertilians, 367 Guanophores, 89 marsupials, 441 Guinea-pig {Cavia porcellus), 445 monotremes, 437 colour vision of, 633 placentals, 494 cornea, 453 snakes, 393 epithelium of, 452 Sphenodon, 383 gonadotrophic hormone, control of, 559 Hare (true), 445

ii'is, 467 cornea, 453 lacrimal passages, 494 nictitating membrane, 493 pineal organ, 716 optic axis, 688 refraction of, 639 calling, 445 retina, rod-rich, 610 diurnality of, 604 vascularization of, 480 jumping, pupils, 612 threshold to light, difference, 618 varying, coloiu" changes in, 21 visual cells, 483 control of, 560 field, uniocular, 672 pupils, 471 Gulls, herring-. See Larus argentatus. Harvestman, 215 navigation by, 64 eyes of, 215 ocular movements in, 696 Harvey, E. Newton, 736 retina, 419 Hatchet -fish. See Argyropelecus sphincter muscle, 407 Hatter ia. See Sphenodon. Gulo. See Wolverine. Hawks, 417 Guppy. See Lehistes. accommodation, 651 Gurnard. See Trigla. distance, judgment of, 702 Gymnophiona. See Apoda. foveae, 417, 659 Gymnothorax, pupil of, 304 lens, 409 Gymnura, brain, 533 scleral cartilaginous cup, 403 Gyrinid beetle. See Whirligig beetle. visual acuity, 662 field, binocular, 684 trident, 684 See also Accipiter, Buteo. H Hearing. See Auditory sense. Hedgehog, 441, 442 Habituation, to light stimuli, 36 colour vision in, 633 Hcemadipsa, 190 eyelids, 491 ocelli of, 134 fundus, PI. XV Hcemopis, ocelli of, 193 optic disc, 486 Hagfishes, 259 retina, pvu'e-rod, 610 See also Myxiyie. vascularization of, 479, 481 Haideotritoyi, degenerate eyes in, 728 visual cells, 482 Haliaetus, 410 Helianthus (sunflower), phototropism in, fundus, 410 41 Halicore. See Dugong. Heliodrilus, conditioning in, 573 Haliotis, ocellus of, 137, 139 Heliophags, 123 Haller's ratio, 401, 450 Heliotropism, 38 Hangnest. See Cacicus. Helix, 142 Hapalemur, diurnality of, 604 circus movements in, 54 .

806 INDEX

Helix Hippolyte varians, 91 eyes of, 142, 197 colour changes in, 91 menotaxis in, 61 rhythmic, 20 aspersa, 198 Hippopotamus, 445 eyes of, 197 cilia lacking, 492 pomatia, ocellus of, 142 cornea, 453 visual cell, 128 eyelids, 491 Heloderma, 359 lacrimal passages lacking, 494 ocular movements of, 694 ocular adnexa, 501 pupils, 359 optic axis, 688 retina, 365 visual acuity of, 654 visual cells, 364 Hirudinea, 190 Helophiliis, 141 Hirudo medicinalis, 193 ocellus of, 140, 141 ocelli of, 133, 193 Hemichordata, 227 Hirundo rustica, 414 eyes of, 227 binocular vision, 683, 684 luminous organs in, 740 colour vision in, 631 nervous system, 530 foveae, 421 See also Balanoglossus pecten, 413, 414 Hemichromis himaculatus, colour reactions, Holangiotic retina, 479 627 Holocephalians, 235, 278 Hemidactylus, 629 accommodation in, 647 colour vision in, 629 eyes of, 290 turcicus, fundus, PI. VI pineal organ, 713 Hetnimysis, telotaxis in, 58 Holosteans, 235, 279, 321 Hemiptera, 218, 220 accominodation, 640, 647 accommodation, static, in, 591 diurnality of, 603 eyes of, 167, 222, 224 eyes of, 321 luminous organs of, 740 See also Amia, Lepklosteus. nervous system, 521, 522 Holothuria, 185 neuro -secretory cells, 555 pigments in, 117 See also Notonecta, Aphis, etc. surinamensis, sensitivity of, 184 Hen. See Gallus domesticus. Holothuroidea, 184 Herons, binocular vision, 675 sensitivity of, 184 See also Ardea, Nycticorax. Homalopsinge, accommodation in, 649 Herpestes. See Mongoose, Homarus, 206 von Hess, Carl, 596, 597 colour changes in, 95 Hesse, Richard, 112, 113 eyes of, 164, 206 organs of, 230 vision of, 578 Heterauxin, 41 Homing, in ants, 68 birds, 703 Heterodon jnodagascariensis, fundus, PI. X 63, pupils, 388 molluscs, 575 wasps, 78 Heterodontus, 286 pigeon, 64 pupil of, 286 hue discrimination in, 619 Heteropods, 199 navigation by, 64 See also Pterotrachea, etc. visual acuity of, 665 Heteroteuthis, biokiminescence in, 742 Homochromatism, 83 Hind-brain, 532, 533 Honey guides, 588 lliodon, visual cells of, 305 Hormonal system, 547 Hippocampus, 310 See also Nevu'o -endocrine system. fovea of, 309, 310 Hormones, 549 ocular movements, 693 biokiminescence and, 22 INDEX 807

Hormones, controlling colour changes, 92 Hyaloid vessels, in snakes, 390 photoperiodism, in animals, 18 teleosts, 299 in plants, 12 Hydra, 182 plant. See Auxins. dermatoptic sensitivity in, 32 See also Pituitary, Sinus gland. nerve-net, 515 Hombill, ocular movements, 696 phototactic reactions of, 571 Horse {Equns caballus), 446 Hydracarina, eyes of, 216 accommodation, 642, 643 vision of, 579 angle gamma, 677 Hydrochoerus capybara. See Capj'bara. anterior chamber, 465 Hydroides, conditioning of, 573 area centralis, 485 reactions of, 573 blood supply to eye, 500 Hydrophinse. accommodation in, 641, 649 brain, 533 pupils, 612, 655 cerebral cortex, 543 Hydrotropism, 33 chiasma, 487 Hydrozoa, 182 cilia, 492 >SVe also Hydra, Obelia, etc. colour vision in, 635 Hygrobates, eyes of, 216 conjunctiva, 491 Hyla, 334 cornea, 453 area centralis, 344 epithelium of, 452 fundus, 341 corpora nigra, 469 iris, 337 eyes of, 447, 449, 450 movement, perception of, 705 lacrimal gland, 493 visual acuity, 661 passages, 494 arborea, 341 nictitating membrane, 493 colour changes in, 86, 105 optic axis, 688 vision in, 628 orbit, 498 ccerulea, eyelids, 345 pectinate ligament, 464 iris, PL III Prejvalski's, 686 pupil, 339 pupils, 471 vasta, pupil, 339 reactions of, 472 Hylobates. See Gibbon. ramp retina, 642, 643 Hymenolcemus malacorhynchus, binocular refraction of, 639 field, 687 retinal vascularization, 478, 480, 481 Hymenoptera, 219, 220 tapetum fibrosum, 457, 458 neuro-endocrine system, 555

visual acuity, 664 jS'ee also Apis, Bombus, Vespa, etc. field, binocular. 689 Hynobius, scleral cartilage in, 347 uniocular, 670, 672 Hyperoodon. See Whale, beaked. See also Equidae. Hyperpiesine, 561 Hovius. circle of, 472 Hypnarce, electric organ of, 751 Humming birds, visual acuity, 662 Hypogeophis, eyes of, 730 See also Calypte. Hypopachus incrassatus, scleral bone in, Humours, four, of Aristotle, 549 335 Hycena, 444, 445 Hypophysis, 538, 557 optic axis, 688 Hypothalamo -hypophyseal system, 552, pupils, 470, 471, 612 556 reactions of, 472 Hypothalamus, 539 brunnea, pupils, 470 hormones and, 550 striata, pupils, 470 reactions of, 541 Hysenidse, 445 Hypotony and hyperpituitarism, 561 Hyaloid vessels, in anurans, 340 Hypsiglena, retina, pure-rod, 610 birds, 415 visual cells, 391 placentals, 476, 477 Hypsiprymnus. See Kangaroo, rat-. .

808 INDEX

Hyracoidea, 446 Insectivores, optic axis, 688 See also Hyrax. retinal vascularization, 479 Hyrax (coney), 444, 446 vision of, 601 diurnality of, 604 See also Mole, Shrew, etc. retinal vascularization, 480 Insects, 217 umbraculum, 469, 470 accommodation in, 591 Hystricomorpha, 445 bioluminescence in, 740, 746 See also Porcupine, Chinchilla, Guinea- rhythmic, 22 pig, etc. blind, 722, 729, 734 Hystrix. See Porcupine. cerebral ganglion, 521 removal of, 525 chromatophores, 86 colour changes in, 82, 93 control of, 555 Ichthyomyzon, 260 rhythmic, 20

visual cells of, 269 ' - vision in, 586 Ichthyophis, 730 dermal sensitivity in, 114 degenerate eyes in, 730 eyes of, compound, 166, 224 Ichthyopsida. See Fishes and Amphi- simple, 224 bians. inactivity in light, 7 Idiacanthus fasciola, 328 larvae of, nervous system, 519 larva. See Stylophthalmus ocelli, 222 Idotea, colour changes, rhythmic, in, 20 vision of, 582 Iguana, 355 See also Caterpillar, Maggot, accommodation in, 651 luminous organs, 742, 746, 747 parietal eye, 715 metabolic rhythms in, 15 visual field, binocular, 682 control of, 556 tuherculata, 358 nervous system, 521, 522

iris, 358 neuro -endocrine system, 552, 555, 556 furrow, 337 ommochromes in, 123 Impennes (Sphenisciformes), 397, 398 orientation of, out-of-doors, 67 ocular adnexa, 425 reproductive cycle of, 17 movements, 696 control of, 556 refraction, 639, 654 retinal pigment migration in, 170 See also Eudyptes, Spheniscus. control of, 556 " Imprinting " in birds, 704 rhythmic, 19 Indris, diurnality of, 604 time-memory in, 22 Infra-red rays, sensitivity to in vipers, vision of, 581 117, 600 visual acuity of, 588 visibility of, in owls, 620, 630 centres in, 524, 525 Infula, in retina of birds, 417 pigments in, 121 Infundibular organ, of Amphioxus, 229 Instincts, 108 Infundibulum, 538 Integumentary pigment. See Pigment, Vesalius's drawing of, 549 integumentary. Insectivores, 441 Interocular transfer of impressions, 698 brain, 533 Intra-ocular filters, 656 cerebral cortex, 543 pressvire. See Ocular tension. ciliary region, 460 Intrascleral plexus. See Circle of Hovius colour vision in, 633 and Canal of Schlemm. diurnal, 604 Invertebrates, accommodation in, 590 degenerate eyes in, 733 eyes of, degenerate, 722, 724, 728, 733 nictitating membrane, 493 morphology, 113 ocular movements of, 696 systematic anatomy, 178 INDEX 809

Invertebrates, nervous system, 511 Jay. See Garrulus. neuro -endocrine system, 552 blue. See Cyanocitta. vision of, 570 Jellyfish, 182, 183 See also under various classes. bioluminescence in, 739 lodopsin, 122 rhythmic, 22 Ipnops, 292, 724 See also Pelagia noctiluca. eyes absent in, 724 myo-epithelial cell, 514 luminous organs, 724, 741 nerve-net, 514 agassizi, 724 nervous control of, 515 Iridocytes, in integument, 89 sense organs, 183 iris, 469 See also Aurelia, etc. tapetum cellulosvim, 459 Jerrymanders, 216 Iridophores, in sea-urchins, 185 eyes of, 216 Iris, characteristics in vision of, 579 Anableps, 324 Johnson, George Lindsay, 428, 429 anurans, 337, PI. II Joseph, cells of, 229 birds, 407, PI. XI Julis, fovea, 309 chelonians, 370, PI. VII ocular movements of, 693 chondrosteans, 317 Julus, circus movements in, 54 crocodilians, 376, PI. VIII Junco hyemalis, reproductive cycle in, 17 dipnoans, 313 holosteans, 321 lacertilians, 357, PI. V K lamprey, 267 marsupials, 439 Kaloula pulchra, iris, 337 monotremes, 435 Kangaroo, 437 placentals, 468 ciliary processes, 439 selachians, 285 rat-, fundus, PL XIII snakes, 386, PI. IX vision in, 601 Sphenodon, 380, 381 Kappers, Cornelius Ubbo Ariens, 508, 509 teleosts, 303, PI. II Keratinization of cornea, in monotremes, urodeles, 347, PI. IV 433 cells, in crustaceans, 165 in placentals, 456 in insects, 168 aquatic, 502 pillars, 464 Kestrel. See Falco tinnunculus. Isoptera, 218, 220 Kinesis, 33 Istiophorus, pupils, 304 See also Photokinesis, etc. Ixodides, 216 King-crab. See Limulus. Kingfishers, bifoveate retina, 418 See also Alcedo, Dacelo. Kiwi. See Apteryx. Klinokinesis, 31, 34 •Jackal (Canis aureus), 445 Klinotaxis, 31, 47 optic disc, 486 definition of, 43 See also Carnivores, Canidae. Koala, 440 Jackdaw. See Corvus, Coloelus monedula. Jacobson's organ, in lacertilians, 368, 599 in snakes, 393, 599 Jaguar {Felis onca), 445 pupils, 471 Labrus, ocular movements, 693 See also Felidae, Carnivores. bergylta, visual pigments, 121 Jastrow illusion, 703 Labyrinths, 534, 690 810 INDEX

Lacerta, accommodation in, 651 Lacrimal passages, characteristics in embryo, median eye, 712, 713 crocodilians, 378 extra-ocular muscles, 368 placentals, 494 lens, 360 snakes, 393 median eye, 715, 718 Lcemargus, 281 transverse muscle, 357 scleral cartilage, 281 visual field, binocular, 680, 682 Lagomorpha, 445 galloti, fundus, 361 angle gamma, 677 monitor. See Varanus. retinal vascularization, 479 muralis, 355 vision of, 601 conus, 362 See also Hare, Rabbit. viridis, conus, 363 Lagostomus. See Vizcacha.

iris, 358 Lamellibranchs. See Bivalves. ocular movements of, 694 Lamina cribrosa, in placentals, 487,488,489 visual responses, 665 ganglionaris, in arthropods, 524 vivipara, colour vision in, 629 Lamna cornubica, 283 vulgaris, conus, 362 iris, 285 Lacertilians, 353 pupils, 287 accommodation in, 651 tapetum, 283 colour changes in, 88 Lampanyctus, visual cells of, 305, 611 vision in, 623, 628 Lampetra, 260

eyes of, 355 j^^., 356 activity of, 34 degenerate, 733 colour changes in, 95 fundi, PI. VI nervous control of, 537, 558 irides, PI. V rhythmic, 20 migration of retinal pigment in, 614 fluviatilis, 260 ocvilar movements in, 694 eyes of, 265 olfactory sense of, 599 median, 716, 717 parietal eye, 715, 716 optic nerve, 270 function of, 719 retina, 268 pupils, contractile, 612 visual cells, 269 refraction of, 639 planeri, eye of, 264 retina, pure-cone, 611 Lamprey, 260 vision of, 599 eyes of, 263 visual acviity of, 661 median, 713, 714, 716, 717 fields, binocular, 680, 682 larva. See Ammocoetes. uniocvilar, 672 visual field, binocular, 678 See also Iguana, Lacerta, Chameleon, See also Cyclostomes, Lampetra, etc. Petromyzon. Lacewings, 219, 220 Lamprocolius chalybeus, iris, 407 Lacrimal glands, characteristics in Lampropeltis getulus, iris, 387 anurans, 345 optic disc, 390 birds, 425 Lamp -shells. See Brachiopods. chelonians, 375 Lampyridae. See Lampyris, Photinus. crocodilians, 378 Lainpyris, bioluminescence in, 746 lacertilians, 367 compound eyes of, 168, 172 marsupials, 441 nod Hit ca, 740 monotremes, 437 splendidula, luminous organs of, 736, placentals, 493 742 urodeles, 349 Lancelets, 228 passages, characteristics in See also Amphioxus. anurans, 345 Langur, 607 birds, 425 colour vision in, 635 INDEX 811

Lanius, 662 Lens (crystalline), characteristics in visual acuity, 662 anurans, 340 Lankester, Edwin Ray, 232, 233 birds, 408, 409 Lantern flies, luminous organs in, 740 cephalopods, 144, 145 Lanthanotus, eyelids, 366 chelonians, 372 Laridae. See Gulls. coelacanth, 315 Larus argentatus, pecten, 413, 414 crocodilians, 377 visual responses, 665 fishes, 276 Lasius, scototaxis in, 60 tubular-eyed, 323 niger, menotaxis in, 69 invertebrate compound eyes. See Lateral geniculate body. See Geniculate Crystalline cone, body. simple eyes, 125, 127, 129 line organs, 534, 690 lacertilians, 360, 361 Latimeria, 235, 278, 315 lamprey, 267 eyes of, 314, 316 marsupials, 439 Latrodectus, 84 monotremes, 436 colour changes in, 84 placentals, 474 Laurence-Moon-Biedl syndrome, 559 selachians, 287 Leander, 578 snakes, 388 colour vision in, 578 Sphenodon, 381 pigments in, 123 teleosts, 304 retinal, migration of, 554 urodeles. 347 reproduction, control of, 555 cuticular, 136, 138, 139, 140, 143 Lehistes reticulatus, area centralis, 309 deformation of, in accommodation, 649 colour changes in, 96, 97 movement of, in accommodation, 644 migration of rods and cones, 614 backward, 644 Leeches, 190 forward, 647 colour changes in, 93 spherical, occurrence of, 606 light-shadow reflex in, 573 vertebrate, origin of, 246 ocelH, 131, 133 yellow, occurrence of, 656 See also Hirudo, Hcemadipsa, etc. Lentiform body of teleosteans, 299 Lemniscus, lateral, 536 Leopard (Felis pardus), 445 Lemur catta, area centralis, 485 eyelids, 491 tapetum cellulosum, 459 pupils, 471 macaco, area centralis, 485 See also Felidae, Carnivores. mongoz, colour blindness of, 635 Lepadogaster, ocular movements, 693 Lemuroidea, 443 Lepas, 208, 209 See also Lemurs, Loris, Galago, etc. adult, degenerate eyes, 722 Lemuroids, nocturnal, 443 larva, eyes of, 209 retina, pure-rod, 610 Lepidoptera, 219, 220 shape of eye, 448 larvae of. See Caterpillar. tapetum cellulosum, 459, 609 See also Butterflies, Moths. visual cells, 482 Lepidosiren, 312 See also Galago, Loris, etc. eyes of, 312 Lemurs (true), 442, 443 forebrain, 239 angle gamma, 677 retina, pure-rod, 610 area centralis, 485 Lepidosteus, 279, 321 colour blindness of, 635 eyes of. 321 eye of, 605 Lepisma, 218 flying. See Flying lemur. circus movements in, 54 optic axis, 688 scototaxis in, 60 Lens (crystalline), characteristics in Lepomis, hue discrimination in, 626 Anableps, 324 threshold to light, difference, 617 812 INDEX

Lepomis Limnesia, eyes of, 216 visual cells, 307 Limulus, 161, 211 Leptinotarsa, 219 activity of, 34 metabolic rhythm in, 16 eyes of, compoimd, 162, 212 Leptodeira annulata, retina, 390 mechanism of, 158 Leptodora, 207 median, 141, 162, 212 eyes of, 163, 209 rudimentary, 163, 212 Leptognathus, pupils, 304, 325 neuro -secretory cells in, 552 Leptoplana, 187 neuro-endocrine system, 552 activity of, 34, 572 orientation to polarized light in, 66 Lepus. See Hare. vision of, 584 Leuckart's ratio, 401 visual pigments in, 121 Leucosolenia, 181 Lineus ruber, 189 light-sensitive cells in, 130, 181 ocelli of, 189 Levator bulbi muscle, in anurans, 345 orientation in, 75 palpebrae superioris, in placentals, 492 Linnaeus, Carl, 8, 9 Lid-fold, in teleosts, 311 flower-clock, 10 Lids. See Eyelids. Lion (Felis leo), 445 Ligament. See Suspensory, Annular, etc. angle gamma of, 677 Light, activation by, 7, 34 area centralis, 485 dermal sensitivity to, 113 cornea, 453 diffuse reaction to, 113 extra-ocular muscles, 495 effect on chromatophores, 89 pupils, 471 metabolism, 7 See also Felidae, Carnivores. movement, 27 Lipophores, 88 pigmentation, 19, 82 Liihohius, conditioning of, 578

inactivation by, 7, 34 Littorina neritoides, 45 perception of, 602 phototaxis in, 45 Light-compass reaction, 61 Lizards. See Lacertilians. Light -differences, discrimination by in- Lizzia, 183 sects, 585 ocellus of, 136 by vertebrates, 617 Llama {Lama), 444, 446 Light-sense, in vertebrates, 602 corpora nigra, 470 Light-sensitive cells, 127, 130 See also Tylopoda, Ungulates. apolar, 128, 131, 133 Local sign, 668 bipolar, 127, 130, 134 Localization in space, 666 in tail of ammocoetes, 263 egocentric, 668 Light-sensitivity, 102, 113 gravitational, 669 in man, photoperiodism in, 559 Locusta, 69 Light-shadow reflex, 45 menotaxis in, 69 in molluscs, 574 ommatidial angle in, 172 in worms, 572, 573 optic tracts, 526 Ligia, 95 vision of, 585 colour changes in, 95 migratoria, ommochromes in, 123 rhythmic, 20 optic ganglia, activity of, 524 eyes of, 165 telotaxis in, 56 Lima, eyes of, 139, 201, 722 Locusts, gregariousness in, 73 Limax, 197 reactions of, 527 maximus, visual cells of, 128 vision of, 583 Limicoline habit, degenerate eyes due to, See also Locusta, Schistocerca. 724 Loeb, Jacques, 26, 28 Limncea, 196 Loligo, 145 nervous system, 528 eyes of, 145, 202 INDEX 813

Loligo Lycoteuthis diadema, 740 luminous bacteria in, 737 luminous organs in, 740 pealii, visual pigment in, 120 Lygodactylus, lens, 361 'oulgaris, 202 Lymantria, larvae, form vision in, 582 Lophortyx californicus, 417 menotaxis in, 61 retina, 417 Lynx (Felis lynx), 444, 445 Loris, slender {Loris gracilis), 443 eye of, 447, 605 tapetum cellulosum, 459 See also Felidse, Carnivores. visual cells, 482 Lytechinus, protection from light in, 39 slow (Nycticebus), 443 pvipils, 472 shape of eye, 448 tapetum cellulosum, 459 M See also Lemuroids, Primates. Lota, retina, rod -rich, 610 Loxia, choroid, 404 Mabuya, transparent eyelids in, 367 Loxodonta africana. See Elephant, Macaca {Macacus). See ]\Ionkey, African. macaque. pileata. See Monkey, toque. Luciferase, 736, 748 rhesus. See rhesus. Luciferin, 736, 748 Monkey, Mackerels. See Scombrid*. Lucifuga, degenerate eyes in, 725 Macrobrachium, retinal pigment, migration Lucioperca, migration of rods and cones in, of, 19 614 Macrogenitosoma prsecox, 719 Lumbriculus, conditioning of, 573 Macroglossa, colour vision in, 587, 588 Lumbricus terrestris, 190 Macronectes giganteus, fovea and infula, cerebral ganglion, removal of, 520 418 conditioning of, 573 Macropodidse, 437 light-sense of, 572 See also Kangaroo, Wallaby. metabolic rhythm in, 16 Macropus. See Kangaroo. nervous system, 519 Macroscelidee, 441 ocelli of, 128, 131, 190 Macula, xanthophyll in, 122 reactions to light, 53, 520 yellow pigment of, 122, 656 tropotaxis in, 53 See also Retma, Fovea, Area centralis. visual pigment in, 120 Maggots, inactivation by light, 7, 34 Luminosity-curve, in insects, 585 klinotaxis in, 50, 51 Luminous bacteria, 737 ocelli of, 137, 139 fungi, 737 Magpie, 403 organs, 736 shape of eye, 402 in arthropods, 740 Malacocephalus Icevis, bioluminescence in, coelenterates, 739 742, 746 echinoderms, 739 Malacostraca, 206 fishes, 737, 741 Malopterurus, electric organ of, 751 molluscs, 740 Malpolon, visual field, binocular, 684 protochordates, 740 Mammals, 429 worms, 739 accommodation in, 652, 653 protozoa, 738 angle gamma in, 676, 677 Lung-fishes. See Dipnoans. brain, 533 Lutianus, colour preference in, 624 transection of, 534 Lutra. See Otter. central nervous system, 532 Lutreola. See Mink. cerebral cortex, 543 Lycosa agricola, 214 removal of, 545 eyes of, 213 ciliary ganglion, 501 814 INDEX

Mammals, colour changes in, seasonal, 21 Mantis religiosa, 589 control of, 560 eyes of, 139, 225 vision in, 632 reactions of, 526 ditirnal, 604 vision of, 589

eyes of, 429 Jf. Manx shearwater. See Puffinus puffinus. degenerate, 733 Manz, glands of, in mammals, 491 habits of, 604 Markhor, reproductive cycle of, 18 lateral geniculate body, 489, 541 Marmosa. See Opossum, mouse. lens capsule, 653 Marmosets, 443 elasticity of, 652 eyes of, 450 marsupial. See Marsupials, fovea, 486 metabolic rhythms in, 13 See also Primates. control of, 560 Marmot, 442, 445 mid-brain, 536 cornea, 453 migration of retinal pigment in, 614 eye of, 447 of visual cells, 616 ocular movements, 696 monotreme. See Monotremes. optic disc, 486 movement, perception of, 705 pupils, 472 neopallium, 543 retina, pure-cone, 612 neuro -endocrine system, 557 vascularization of, 479 nocturnal, 604 visual acuity of, 664 ocular movements of, 696 cells, 483 optic axis, 688 Marsupials, 429, 437 lobes, 535 accommodation lacking in, 640 thalamus, 540 arhythmic, 604 pineal organ, 716 colour vision in, 632 function of, 718, 719 fundi, PI. XIII placental. See Placentals. eyes of, 438 primitive, 236 lateral geniculate body, 489, 490, 541 pupillary reactions of, 700 nocturnal, 604 receptor-effector system, 514 optic axis, 688 refraction of, 639 refraction of, 639 reproductive cycle in, 18 vision of, 601 control of, 559, 560 Marsupium. See Pecten. spatial judgments of, 704 Marten (Martes), 445 tectum, 536 colour blindness of, 634 telencephalon, 543 See also Mustelidae. threshold to light, difference, 618 Marthasterias glacialis, PI. I vision of, 600 eye-spot of, PL I visual acuity of, 663 Martlet (Chelidon), visual acuity of, 662 field, binocular, 687, 689 Mast, Samuel O., 26, 29 uniocular, 672 Mastigophora. See Flagellata. pathways, 540, 544 Mastigoproctus giganteus, activity of, 34 Mammillo-infundibular nuclevis, 557 Matthiessen's ratio, 277 Manatee, 446, 502 Mayflies. See Ephemeroptera. retinal vascularization, 480 Mazes, 569, 624 See also Sirenians. conditioning by, in ants, 70 Mandrill (Mandrillus), 443 crustaceans, 578, 579 refraction of, 639 myriapods, 578 See also Primates. snails, 575 Mangabey, colour vision in, 635 worms, 573 Mania. See Pangolin. Mechano-receptors, 116 INDEX 815

Median eyes, 711 Metopoceros cornutus, conus, 363 of lamprey, 716, 717 fundus, 361, PI. VI lizards, 716, 718 Metndium, phototactic reactions of, 571 Sphenodon, 716 Microchiroptera, 443 Medulla, external, 524 See also Vampire bat, Vespertilio. internal, 524 Micrococcus pJwsplwreus, luminescence of, tenninal, 524 738 MedusEe, 182 Micropus apus, 407 nerve-trunks in, 516 ciliary muscle, 407 See also Jellyfish. fovea, 418 Medusoids, 182 pecten, 412 sense-organs of, 182 Microspira photogenica, luminescence of, Megabunus diadema, 215 738 Megachiroptera, 443 Microtus. See Vole, field-. choroidal papillte, 459 Mid-brain, 532, 534 corrugated retina, 643 Migration of birds, 17 retinal tapetum, 459, 608 of pigment. See Pigment, migration of. See also Flying fox. of rods and cones. See Visual cells, Megalobatrachus 7naximus, 349 migration of. eyes of, 349 Migratory eyes in fishes, 328 Meganyctiphanes, bioluminescence in, 740 Millipede, 210 Megaptera. See Whale, hump-back. eyes of, 210 MegerUa, eyes of, 195 See also Myriapods. Meibomian glands, in placentals, 491 Milvus, 420 Melanerpes erythrocephahis, pecten, 412 green oil-droplets, 420 Melanin, 89, 118 Mimicry, 83 Melanoblasts, 118 Mimosa pudica (sensitive plant), response Melanophores, 87 to light, 511 in iris, of anurans, 337 Mink, pvipils, 472 of snakes, 386 Minnow. See Phoxinus. in sclera, of snakes, 385 Miopiesine, 561 Melanoplus, electroretinographic re- Misgurnus, 310 sponses, 586 optic nerve, 310 Meleagris gallipavo, retina, 417 Mites, 216 Meles. See Badger. eyes of, 216 Melopsittacus undulatus, iris, 407 water, eyes of, 216 Melursus. See Bear, sloth-. Mitosis, diurnal rhythm in, 13 Membrana vaseulosa retinae, 482 Mneyniopsis, bioluminescence in, 748 in anurans, 341 Mnemotaxis, 31, 78 dipnoans, 313 definition of, 44 holosteans, 321 Moa, 604 pol;y^terini, 320 extinction of, 604 snakes, 290 Mobulida?, pupils, 287 teleosts, 299, 300 Mole (true), 441 Menotaxis, 31, 60 eyes of, 732, 733 definition of, 44 optic axis, 688 Merangiotic retina, 479 disc, 486 Mesencephalon. See Mid-brain. retinal vascularization, 479, 481 Metabolism, diurnal rhythm of, 13 golden, 442, 443 effect of light on, 7 eyes of, 733 regulation of, 555, 556, 560 marsupial, 437 Metazoa, 181 eyes of, 733 Metencephalon, 532 scleral cartilaginous nodules, 438 816 INDEX

Mole, rodent, eyes of, 733 Monotremes, optic axis, 688 water. See Desman. vision of, 600 Moll's glands, in placentals, 492 Moon, navigation by, 73 Molluscs, 195 Mordacia, 260 accommodation in, 590 eyes of, 265 blind, 723, 729 Mormyridae, 294 cerebral ganglion, 527, 528 scleral cartilage in, 294 activity of, 524 Mosaic, retinal, 656, 705 deep-sea. See Deep-sea molluscs, theory, 155, 170 dermal sensitivity in, 114 Mosquitoes, eyes of, 220 eyes of, 196 orientation to polarized light, 66 degenerate, 723 See also Diptera, Aedes, Culex, etc. inverted retina in, 147 Motacilla alba, 660 luminous organs in, 737, 740, 746 summation, retinal, 660 metabolic rhythms in, 15 Moths, 219, 581 nerve-net, 515, 516 behaviour of, 63 nervous system, 527, 528 eyes of, 159 neuro -endocrine system, 550 olfactory sense of, 581 neuro -secretory cells, 552 retinal pigment, migration of, 170 reproductive cycle in, 17 vision of, 585 vision of, 574 Moulting, photoperiodism and, 21, 555, visual centres, 529 556, 560 See also Cephalopods, etc. Mouse, 445 Mongoose, 445, 472 colour blindness of, 633 pupils, 472 eyelids, 491 Monkeys, 443 field-, colour blindness of, 633 capuchin, 443 Harder's gland, 494 colour vision in, 635 lacrimal gland absent, 493 lens capsule, 653 Moll's gland absent, 492 visual acuity of, 665 ocular movements of, 696 howling, 443 optic axis, 688 macaque, 443 nerve-head, 488 iris vascularization, 468 photoperiodism in, 18 nictitating membrane, 493 refraction of, 639 pupillary reactions, 472 retina, rod-rich, 610 retractor bulbi, 495, 496 vascularization of, 479, 481 New World, 443 visual acuity, 663 nocturnal. See Nyctipithecus. cells, 483 Old World, 443 Movement, perception of, in cephalopods, rhesus, colour vision in, 635 576 fovea, 486 in insects, 589 retina, 483 vertebrates, 705 visual acviity of, 665 stroboscopic, 706 spider, 443, 689 Movements, ocular. See Ocular move- colour vision in, 635 ments. toque, fundus, PI. XIV Mucopolysaccharide, in anterior chamber Monodon. See Narwhal. of owls, 404 Monotremes, 429, 431 Mugil, colour preference in, 625 accommodation lacking in, 640 eyelids, 311 colour vision in, 632 ocular movements in, 693

eyes of, 431 j^. corsida, accommodation in, 654 fundi, PL XIII Muller (H), fibres (cells) of, 248 nocturnality of, 604 development of, 240 INDEX 817

Miiller (H), muscle of (ciliary), in birds, Myomorpha, 445 406 See also Mouse, Kat, etc. (orbital), in mammals, 496 Myriapods, 210 (palpebral), in mammals, 492 blind, 729 Johannes, 154 eyes of, 151, 210 Miiller-Lyer illusion, 703 luminous organs in, 740, 745 Murex, 197 neuro -endocrine system, 552 ocelli of, 142, 197 vision of, 578 regeneration of eye, 136 visual centres, 524 Miis. See Mouse. Myrmecobiiis. See Ant-eater, banded. Musca domestica, 172 MyrmecopJiaga. See Ant-eater, giant. eyes of, 167, 172 Mysids, 58 maggot of, 50 telotaxis in, 58 klinotaxis in, 50 Mystacoceti, 446 ocellus of, 137, 139 Mytilus, 200 visual acuity of, 588 sense organs of, 200 Muscles, extra-ocular, characteristics in Myxicola cesthetica, ocelli of, 191 aniu-ans, 345 Myxine gluiinosa, 114, 734 birds, 424, 425 degenerate eyes of, 734 fishes, 277, 278, 691 dermal sensitivity of, 114 hammerhead shark, 327 secretory mechanism of, 267 lacertilians, 368 Myxinoids, degenerate eyes in, 734 lamprey, 271 labyrinths, 534 m.onotreines, 437 median eyes absent, 713 placentals, 494, 495 See also Bdellostoma, Myxine. selachians, 290 Myzus, colour vision of, 587 teleosts, 312 See also under various }nuscles. Mustela erminea. See Ermine. N nivalis. See Weasel. Mustelida?, 445 Naja tripudians, 386 lacrimal passages absent, 494 fundus, PI. X nictitating membrane, 493 Narwhal, 446 pupils, 472 Nasal asymmetry, 674 Alustelus, 285 Nasua. See Coati. area centralis, 289 Native cat. See Dasyure. chromatophores, 96 Natrix. See Tropidonotus. pupils, 285, 286 Nautilus, 130 tapetum, 283 ocellus of, 137, 201 visual cells, 288 Navigation by birds, 64 antarcticus, pupil of, 286 pecten and, 416 Mya arenaria, 131 Necrojjhorus, 219 light -shadow reflex in, 574 eyes of, 172 ocelli of, 131, 200 Necturus, 349 visual pigment in, 120 eyes of, 349 Myelencephalon, 532 violet rods, 350 Myliobatis, 283 Nematodes, 187 eyes, 281 sense organs of, 190, 734 pupils, 287 Nemertines, 187 visual cells, 288 bioluminescence in, 739 Myocastor coypus. See Coypu. nervous system, 519 Myo-epithelial cells, 513, 514 sense organs of, 189 Myogale. See Desman. Nemestrinus, colour vision in, 635

S.O.- VOL. I. 818 INDEX

Neoceratodus, 312 Nictitating membrane, characteristics in eyes of, 312 crocodilian*^, 378 retina, pvire-cone, 611 lacertilians, 367 Neodiprion, orientation to i:iolarized light marsupials, 441 in, 66 placentals, 492 telotaxis in, 57 platypus, 437 Neognathfp. See Carinata:>. selachians, 289 Neopallium, 543 Sphenodon, 383 Nereis, 190, 191 false, in teleosts, 312 cerebral ganglion, removal of, 520 in anurans, 345 conditioning of, 573 interposition of, in accominodation, nervous system, 520 643 ocelli of, isS, 191 Night -jar. See Caprinmlgus. Nerve trunk-pathways, 513, 516 Noctiluca, 179, 180, 738 in coelenterates, 516 luminescence of, 738 echincderins, 516 miliaris, luminescence of, 738 Nerve-net, subepithelial, 512, 514 Nocturnal animals, 602, 721 in balanoglossids. 515, 517 eye, characteristics of, 605 coelenterates, 512. 514, 515 retina of, 609, 610 m.olluscs, 515 Notechis, eye of, 385 worms, 515, 518, 520 anterior segment, 386 Nerves. See tmder various nerves (Optic, visual acuity of, 657 Corneal, etc.). Notonecta, 73 Nervous system, 511 circus movements in, 54 characteristics in colour vision of, 587 arthropods, 521, 522 migration of visual cells, 170, 614 coelenterates, 514, 515 orientation of, 73 echinoderms, 516 Notoryctes typhlops. See Mole, marsupial. molluscs, 527, 528 Notropis, colour vision in, 625 protochordates, 530 Nucleus lateralis, 557 vertebrates, 530 pre-opticus, 557 worms. 518, 519, 520 Nudibranchs, 196 central, 530 bioluminescence in, 740 development of, 531 Numida pucherani, retina, 417 evolution of, 512 Nycticebus. See Loris, slow. ganglionic, 517 Nycticorax, 413 Neurobiotaxis, 509, 699 pecten, 413 Neuro -endocrine systein, 550 Nyctipithecus, 443 of crustaceans, 552 area centralis, 485 insects, 555 fovea, pure-rod, 486 vertebrates, 556 nocturnal ity of, 604 function of, 558 retina, pure-rod, 482, 610 Neurohumoral activity, 550 tapetviin fibrosum, 458, 609 Neurohypophysis. See Hypophysis. Neuropile, 518 O Neuroptera, 219, 220 Nevirosecretion, 550 Obelia, 182 Neurosecretory cells, 550, 551 Ocellus. See Eye, simj^le. Newts, 346 Octavus system, 535 See also Urodeles, Triturus. Octopus, 93 Nictitating membrane, characteristics in colour changes in, 85, 92, 93 birds, 423, 424 conditioning of, 576 chelonians, 374 eyes of, 144, 202 INDEX 819

Octopus Ommatidial angle, 172, 173 optic lobes, 529 eye. See Compound eyes, reactions of, 528 simple, 159 vision of, 575 Ommatidium, 155 vulgaris, 202 Ommatin, 123 Ocular movements, 689 Ommin, 123 involuntary, 690 Ommochromes, 123 voluntary. 692 Onchidiuyn, 199 in amphibians, 345, 694 accommodation in, 590 birds, 425. 695 eyes of, 148, 199 chelonians, 374 homing ability of, 575 fishes, 278, 693 Oniscus, metabolic rhythm in, 15 lacertilians, 368 Ontogeny of vertebrate eye, 239, 240 mammals. 497, 696 Onychophores, 204 co-ordination of, 693 eyes of, 205 reptiles, 694 degenerate, 724 snakes, 393 nervous system, 521 tension, diencephalon and, 560 vision of, 578 diurnal rhythm in, 14, 561 See also Peripatus. Oculiferous tubercle, in harvestmen, Operculum (pupillary). 612 215 in catfishes, 304, 329

j errymanders, 216 flat-fishes. 329 sea-spiders, 217 mammals, 469, 470 Oculoir.otor centres, 534 selachians, 287 nuclei, 535, 699 Ophidians, 353 Ocydpoda ippens, 205 accommodation in, 648 Odonata, 220, 225 colour training of, 628 eyes of, 373 eyes of, 222, 225 j^., 385 See also Aeschna. Anax. degenerate, 731 Odontoceti, 446 fundi, PL X irides, PI. IX Odontosyllis, bioluminescence in, 741 ocular movements, 694, 695 (Edicnenius, pecten, 412 olfactory sense in, 599 Oil-droplets, colour vision and, 631 pineal organ, 716 occurrence of, 631, 656 pupils, contractile, 612 Okapi (Okapia), nictitating membrane, refraction of, 629 496 vibi'atory sense in, 599 Olfactory centres, 543 vision of, 599 sense, of bees, 588 visual acuity of, 661 birds, 600 field, binocular, 682 fishes, 598 Ophiops, eyelids in, 366, 367 gastropods, 574 Ophiotettix, 223 insects, 581 Ophisauriis ventralis, fundus, 362 mammals, 601, 733 Ophiuroidea, 184 reptiles, 599 Ophrycessa superciliosa, iris, PL V

predominance of, 103 ' Ophthalmic artery, in anurans, 340 spatial judgments and, 667 in placentals, 498

j Oligochaetes, 190 Opiliones. [ See Phalangida. bioluminescence in, 739 Opisthobranchs, 196 j

conditioning of, 573 ! neuro -secretory cells, 552 nervous system, 519 Opisthoproctus, 324 ocelli, of, 190 j tubular eyes 324

See also Lumbricus. 1 visual field, binocular, 680 820 INDEX

Opossum, 437 Optic nerve, characteristics in Australian, lateral geniculate body, 489, urodeles, 350 490 decvissation of fibres. See Chiasmal pupils, 612 decussation, eye of, 605 septal system of, 487 mouse, ciliary muscles, 439 pedicle, in selachians, 290 visvial cells, 441 pits, 239 Virginian, 439 thalamus, 538 ciliary muscles, 439 vesicles, 239, 537, 711 colour blindness of, 633 Optical system, of vertebrates, 605, 638 fundus, PI. XIII duplicated, 641 nictitating membrane, 441 Optics of compound eye, 170 optic axis, 688 Optomotor reaction, 568 retinal circulation, 440 in crustaceans, 578 tapetum, 440, 608 insects, 73, 583, 584 visual acuity of, 665 colour vision and, 587 Optic axis, 675, 688 light -differences and, 585 chiasma. See Chiasmal decussation, visual acuity and, 588, 589 disc, characteristics in spiders, 580 birds, 410 vertebrates, colour vision and, 623 chelonians, 372 movement, perception of, and, crocodilians, 378 706 lacertilians, 362 Orang-utan, 443 marsupials, 440 See also Apes, Primates. monotremes, 436 Orbicularis oculi, in placentals, 492 placentals, 486 Orbit, characteristics in polypterini, 320 anurans, 346 selachians, 288 birds, 423, 424, 425 snakes, 390 chelonians, 375 Sphenodon, 381 crocodilians, 378 teleosts, 310 hammerhead shark, 327 urodeles, 347 lacertilians, 368 ganglia, in arthropods, 523, 524, 525 lamprey, 270 lobes, of arthropods, 521, 525, 526, 584 monotremes, 437 of birds, 535 placentals, 497 cephalopods, 528, 529, 576 selachians, 290 fishes, 534 snakes, 393 mammals, 535 Sphenodon, 383 reptiles, 535 teleosteans, 312 norve, characteristics in Orbital axis, 675, 676 anurans, 344 ganglion. See Ciliary ganglion, birds, 422 nerves, in placentals, 5i31 crocodilians. 378 sinus, in rabbit, 500 dipnoans, 313 Orca. See Whale, killer holosteans, 322 Orectolobus, pupil, 286 lacertilians, 366 Organelle, 129 lamprey, 270 Orientation angle, in menotaxis, 61 monotremes, 436 to light, 27 placentals, 486, 488 methods of, 31 selachians, 288 See Phototaxis, etc. snakes, 392 of insects, 67 Sphenodon. 383 of plants, 27 teleosts, 310 polarized, 66 INDEX 821

Orientation, to visual pattern, 73 Owls, visual acuity of, 662 visual, 667 field, binocular, 682, 683, 684 Ornithorhynchus. See Platypus. uniocular, 670, 672 Orthokinesis, 34 See also Bubo, Otus, Strix. Orthoptera, 218, 220 Ox. See Cattle. eyes of, 223 Oxybelis, iris, 371 See also Blattella, Loc^tsta, Di.vippus, Oysters, 196 etc. light-shadow reflex, 574 Orycteropiis. See Aard-vark. pearl. See Avicula. Oryctolagus. See Rabbit. Os opticus of birds, 403 Osseous plaques (scleral), in chondro- steans, 317 in Latimeria, 315 Pachydactylus niaculatus, eyelids lacking Ossicle of Gemminger, in birds, 403 in, 367 Ossicles, scleral, accommodation and, 649 Palcemon, colour changes in, 91 in birds, 403 rhythmic, 20 chelonians, 369 Palcemonetes, colour changes in, 94 lacertilians, 356 retinal pigment, migration of, 555 Sphenodon, 380 Palfeocortex, 543 teleosts, 294 Palseognatha?. See Ratitse. occurrence of, 450 Pallial eyes, in bivalves, 201 Osteichthyes, 234, 235, 278 Pan. See Chimpanzee. {Ailurus), 445 eyes of,' 291 Panda See olso Teleosteans, etc. pupils, 471 giant (Ailuropoda), nictitating mem- Osteolcemus tetraspis, iris, PL VIII brane, 493 Ostracods, 207 Pandalus, visual pigments in, 121 eyes of, 209 Pangolin, 442, 445 luminous organs in, 740, 746 Pantodon, visvxal field, binocular, 680 See also Cypris, etc. Pantopoda. See Pycnogonida. Ostrich, African. See Struth io. Papio. See Baboon. American. See Rhea. Paracentrotus Hindus, sensitivity of, 184 eye of, 399 Paralichthys albiguttus, colour changes in, Otariidae. See Sea-lions. 92 Otter, 445 Paramoecium, 179, 180 accommodation in, 654, 655 geotaxis in, 45 optic axis, 688 klinokinesis in, 36 shrew. See Shrew, otter-, modified by electric shock, 571

sphincter muscle, 468 bursar is, reproductive cycle in, 16 Otus bakkamcena, iris, PI. XI Paraj^ineal organ. See Parietal organ. Owls, ciliary muscle, 407 Parasites, external, degenerate eyes in, colour vision in, 630 734 eyes of, 399, 605 internal, degenerate eyes in, 733 immobility of, 695 Paraventricular nucleus, 557 shape of, 402 Parazoa, 181 fovea, 417, 418 See also Leucosolenia. iris, 407 Parietal eye, of lamprey, 713, 716, 717 lens, 409 lizard, 715, 716, 718 pecten, 411 Sphenodon, 715, 716 threshold to light, 674 origin of, 242 absolute, 617 foramen, in Sphenodon, 715 visibility to infra-red, 620, 630 organ, 538, 713 822 INDEX

Parietal organ, accessory, 715 Pectinate ligament, characteristics in function of, 719 marsupials, 439 Parrots, eyelids, 424 placentals, 463, 464, 469 eyes of, 399 Pectunculus, ocelli of, 151, 201 ocular movements of, 696 Pediculus, 218 reproductive cycle in, 17 ocelli of, 139 visual field, binocular, 684, 685 scototaxis in, 60 See also Chrysotis. Pedipalpi, 214 Pars intercerebralis, in insects, 555 See also Whip-scorpions. Parus, panoramic vision in, 683 Pedunculate body, in arthropods, 521, 524 visual acuity, 663 Pelagia, myo -epithelial cells in, 513 Passer domesticus, 408 noctiluca, bioluminescence in, 739, 744, ciliary venous sinus, 408 745, 748 colour vision of, 630, 632 rhythmic, 22, 747 orbit and brain, 424 Pelecanus, 410 reprodvictive cycle in, 17 conspic Hiatus, fundus, 410 summation, retinal, 660 Pelobates fuscus, pupils, 339 visual acuity of, 662 Pelomyxa, effect of light on, 7 cells, 419 latent period in, 36 Passeriformes, accommodation in, 651 Penguin, 398 bifoveate retina, 418 rock-hopper. See Eudyptes. eyes, shape of, 402 See also Impennes. pecten, 412 Peragale. See Bandicoot, rabbit, time-memory in, 22 Perameles. See Bandicoot. See also Corvidse, Hirundo, Passer, etc. Perca, ocular movements of, 692 Passerita prasina, 674 fluviatilis, optomotor reaction of, 706 iris, PI. IX Perception of colour, 619 pupil, 388, PI. IX depth, 667 visual field, binocular, 684 form, 637 Patella, 197 light, 602 homing ability of, 575 movement, 705 ocelli, 137, 197 size, 667 Paurangiotic retina, 480 space, 666 Pauropus, 211 Perch. See Perca. eyes lacking in, 729 climbing. See Anabas. Pearl-fish. See Encheliophis. Percidse, retinal tapetum in, 305, 612 Pearly nautilus. See Nautilus. See also Perca, Lucioperca. Peccary (Dicotyles), 445, 458 Perichceta, phototaxis, in, 45 See also Suoidea. Periophthalmus, 326, 694 Pecora. See Ruminants. accommodation in, 655 Pecten of birds, 410 annular ligament, 295, 296 function of, 415 eyes of, 326 histology of, 414 ocular movements of, 694 pleated type, 411, 412 Peripatopsis alba, degenerate eyes of, 724 vaned type, 411 Peripatus, 139, 204 Pecten (scallop), 200 nervous system, 521 ocelli of, 148, 200 eyes of, 138, 205 sensory reactions of, 103 Periplaneta, response to light of, 34, 114 vision of, 575 Perissodactyla, 446 Pectinate ligament, characteristics in pupils, 472 chelonians, 372 retinal vascularization, 480 crocodilians, 376 See also Equidae, etc. lacertilians, 359 Periwinkle. See Littorina. INDEX 823

Pernis apivorus, iris, 408 Phoenicopterus Persistence -time of vision, 705 retina, 419 Petaurus. See Flying phalanger. ruber, iris, 407 Petrogale. See Wallaby. Pholas, bioluminescence in, 736, 740, 745, Pefromyzon 7)iarinns, 260, 716 748 brain, 533 ocelli of. 200 visual pigment in, 120 eyes of, 265 _ff. larva. See Ammocoetes. Pholidota, 445 uveal tract, 266 Pholis, fovea, 310 visual cells, 269 Phosphorescence, 747 See also Cyclostomes. Photinus, 219 Phseommatin, 123 bioluminescence in, 742, 749 Phalacrocorax, 404 rhythmic, 22, 747 accommodation in, 652. 655 vision of, 585 annular pad, 409 pyralis, bioluminescence in, 740 ciliary muscle, 407 telotaxis in, 58 harderian gland, 425 Photoblepharon, luminous organ in, 737,

iris, 407 738 lens, 409 Photocytes, 251

^ ocular movements of. 696 Photoglyctemic reflex, 560 scleral ossicles, 404 Photokinesis. 31, 32. 33 sphincter muscle, 407 Photo-mechanical changes in retina. 614, bougainvillii, iris, 407 615 Phalanger, 437 Photoperiodism, 7 fij'ing. See Flying phalanger. in animals, 13 spotted (cuscus), 438 bioluminescence and. 21, 747 vulpine. See Opossum, Australian. blood constituents and, 13 Phalangeridte, 437 centres controlling, 14, 550 Phalangida, 215 general activity and, 15 Phalaris canariensis (grass), phototropism light sensitivity and, 559 in, 40 metabolism and, 13, 555, 556. 560 Phascolarctin;p. 437 mitosis and, 13 See also Koala. ocular tension and, 14, 560 Phascolomyinse, 437 pigment migration and, 19, 554, See also Wombat. 556, 558 Phengodes, hnninescence of, 739 sexual cycle and, 16. 555, 556, 559 Philatithus triangulinn, mnemotaxis in, 78, temperature and, 13 79 lu'inary output and. 13 Phobotaxis, 31 in plants, 9 Phoca. See Seal. Photophores, 746 Phoccena. See Porpoise. Photopigments. .See Pigments. Phocidse, 445 Photoseixsitivity, 4. 113 in. 641 accommodation diencephalon and, 537 cornea, keratinized, 456 Photostasis, 544 eye of, 449 PJwtostomkis guernei, luminous organs in, lens, 474 743 ocular adnexa, 501 Photosynthesis, 4 optic axis, 688 disc, 486 Phototaxis, 31. 32, 42 pupil, 470, 641, 655 types of, 47 refraction of, 639 Phototropism, 31. 32, 38 retina, pure-rod, 610 in animals, 39 Phoenicopterus, 407 in plants, 38, 40 824 INDEX

Photurus pennsylvanica, luminous organ Pig, vitreous, 476 of, 747 Pigeon. See Cohimba. Phoxinus, 294 homing. See Homing pigeon. colovir changes in, 92, 96 Pigment (s), 117 diencephalon and, 537 activity of plants and, 12 vision in, 625, 626 carotenoid, 88, 118 metabolic rhythm in, 15 dermal sensitivity and, 114, 117 multiple cones in, 308 integumentary, 85 stroboscopic movement and, 706 migration of, 82 threshold to light, difference, 617 control of, in crustaceans, 554 visual acuity of, 660 insects, 555 Phronima sedentaria, 160 vertebi-ates, 558 eyes of, 160 pineal organ and, 719 Phrynoinerus, pupils, 339 rhythmic, 19 Phrynosoma, 365 melanin, 87, 118 colour changes in, 98 retinal, in compound eyes, 165, 168 control of, 558 migration of, in crustaceans, 165 rhythmic, 20 control of, 554 fovea, 365 rhythmic, 19 Phyllirrhce, bioluminescence in, 740 in insects, 170 Phyllopods, 207 control of, 556 See also Branchiopods, Apus, etc. rhythmic, 19 Phyllorhynchus, pure -rod retina, 610 in vertebrates, 614, 615 Phyllurus milii, visual pigments in, 122, control of, 558, 559 252 visual, 118 Phylogeny of vertebrate eye, 237 yellow, in cornea of Amia, 321, 656 Physeter. See Whale, sperm. of teleosts, 295, 656 Physignathiis, fovea, 365 of macula, 122, 656 iris, PI. V Pigmentary degeneration, primary, light Phytohormones, 39, 549 sensitivity and, 559 Pieris, colour vision of, 587 photoglycaemic reflex and, 560 luminosity -curve of, 586 Pigmentation, effect of light on, 82 vision of, 585 Pika. See Hare, calling. Pig {Sus), 445 Pineal apparatus, 711, 712 angle gamma, 677 eye, in fishes, 713 blood supply to eye, 499, 500 lamprey, 713, 716, 717 ciliary ganglion, 501 young frog, 714 region, 461, 462 origin of, 242 conjunctiva, 491 gland, Descartes's conception, 711 glands of, 491 in mammals and birds, 716 cornea, 453 man, 715 epithelium of, 452 reptiles, 716 harderian gland, 494 organ, 538, 713 lacrimal gland, 493 hormones and, 550 lens, 474 fvinction of, 718 Manz's glands, 491 tumours, 719 Moll's glands, 492 Pinnipedes, 445 nictitating membrane, 493 choroid, 457 optic axis, 688 eyes, shape of, 448 orbit, 498 lacrimal passages lacking, 494 pectinate ligament, 464 lens, 474 retinal vascularization, 479 ocular adnexa, 501 sphincter muscle, 468 pectinate ligament, 464 INDEX 825

Pinnipedes, pupils, 470, 612 Plants, long-day, 11 refraction of, 639 photoperiodism in, 9 retinal vascularization, 479 photoreceptors in, 116 sphincter muscle, 468 photosynthesis in, 4 tapetum cellulosuni, 457, 459, 609 short -day, 11 Pipa americana, 334, 339 Platyhelminthes, 187 pupils, 339 contraction in light, 7 Piscicola, ocelli of, 193 sense organs of, 188 Pithecanthropus, 445, 755 See also Turbellarians, etc. Pithecia. See Saki. Platypus, 430, 431 Pithecus. See Langur. ciliary body, 434 Pituitary gland, 538 eye of, 432 hormones and, 550 posterior segment of, 433 intra-ocular pressure and, 561 retina, 435 in vertebrates, 557 scleral cartilage, 433 hormone, photoperiodic changes and, Plecoptera, 218, 220 19 Plecostomus, pvipil, 304, 329 seasonal changes and, 21 Pleiirodeles, iris vascularization, 347 Placentals, 429, 441 Pleuronectes, ocular movements in, 693 colour vision in, 633 flesus, pupil, 304 decussation, chiasmal, 698 platessa, camouflage in, 83 diurnal, 604 Plexippus sinuatus, eyes of, 212 eyes of, 446 #., 607 Plusia gamma, olfactory sense of, 581 fundi, PL XIV, XV pigment migration in, 19 nocturnal, 604 control of, 556 panoramic vision, 686 Podargus, pecten, 412 pujiils, contractile, 612, 613 Poikilochromic animals, 82 spatial judgment, 704 Polarized light, orientation to, 66 vision of, 601 mechanism of, 174 visual field, binocular, 687, 689 Polecat {Putorius putorius), 444, 445 See also Mammals. colour blindness of, 634 Placode theory of origin of vertebrate eye, threshold to light, difference, 618 246 Polycelis coronata, ocelli of, 188 Placoderms, 234, 235 Polychsetes, 190 Placophora, 196 accommodation in, 591 ocelli of, 196 bioluminescence in, 739, 745, 748 See also Chiton. colour changes in, 93 Plagiostomum, activity of, 34 conditioning of, 573 Plaice. See Pleiironectes platessa. degenerate eyes in, 729 Planaria gonocephala, ocellus of, 134 light-shadow reflex in, 573 phototactic reactions of, 572 nervous system, 520 lugubris, phototaxis in, 43, 45 ocelli of, i91 maculata, tropotaxis in, 55 reproductive cycle of, 18 torva, visual cells of, 128, 134 Polyclad worms, 187 Planarians, 34, 187 eyes of, 188 cave-dwelling, eyes of, 724 neuro -endocrine system, 552 nervous system, 519 See also Leptoplana. orthokinesis in, 34 Polyipnus, optic nerve of, 310 phototactic response in, 33, 572 Polyodon, 315 Planes, colour changes in, 92 Polyophthahnus pictus, ocelli of, 130, 191 Plants, distinction from animals, 510 Polypedates reinwardti, pupil, 339 floral initiation in, 10 Polyphemus, 209 hormones in, 12, 39 eyes of, 163, 209 826 INDEX

Polypterini, 235, 278, 315 Primates, diurnal, 604 eyes of, 320 extra.-ocular mvxscles, 495 Polypterus, 278, 320 eyes of, 450 eyes of, 320 fovea, 486, 659 median eye of, 713 harderian gland, 494 Polyzoa, 194 iris vascularization, 468 larva, ocelli of, 195 lateral geniculate body, 489, 490, 541 Pomolobus, eyelids in, 311 lens, 474 Pongo. See Orang-utan. capsule, 653 Pontellopsis regalis, eyes of, 159, 209 svitures of, 474, 475 Popillia, response to light, 34 Moll's glands, 492 Porcupine, 442, 445 neviro-endocrine system, 557 colour blindness of, 633 nictitating membrane, 493 eye of, 447 nocturnal, 604 optic axis, 688 occipital cortex, removal of, 546 retinal vascularization, 480 ocular movements of, 696 Porichthys, luminous organs of, 746 orbit, 498 Porifera. See Sponges. pectinate ligament, 464 Porphyropsin, 122 pineal organ, 715 Porpoise, 446 pulvinar, 542 cornea, 453 pupils, 471 See also Cetaceans. reactions of, consensual, 700 Porthesia caterpillar, phototaxis in, 46 refraction of, 639 Portunus, colour changes in, 92 retina, 483, 616 Postural reflexes, 690, 691 vascularization of, 477, 479 Potamilla, ocelli of, 192 retractor bulbi, 495, 496 Potamogale. See Shrew, otter-. spatial judgments of, 704 Potto, 443, 607 summation, geniculate, 611 See also Lemuroids. vision of, 601 Pouchetia, eye -spot of, 126 visual acuity of, 663, 664 Prairie-dog, 445 cells, 482,' 483 pupils, 472 field, binocular, 689 visual cells, 482 uniocular, 670 Prawns, 166 zonular fibres, 475, 476 eyes of, 163, 206 Pristis, 279 luminous organs of, 742 Proboscidea, 446 See also Hippolyte, Palmynon. See also Elephants. Praying maiitis. See Mantis religiosa. Procellaria pelagica, 420 " Preference " technique, 568 green oil-droplets, 420 colour vision and, 623 Proctacanthns, circus movements in, 54 Primates, 443 telotaxis in, 59 accommodation in, 654 Procyon. See Raccoon. angle gamma of, 677 Procyonidse, 445 area centralis, 485 pupils, 471, 472 canal of Schlemm, 473 Pronghorn, lacrimal gland absent in, 493 cerebral cortex, 543 See also Ruminants. removal of, 545 Propithecus, diurnality of, 604 chiasmal decussation, 487, 698 Prosencephalon. See Fore-brain. ciliary cleft, 463 Prosimians, 443 muscle, 462 area centralis, 485 processes, 467 diurnal, 604 region, 460, 463 eyes, shape of, 448 colour vision of, 635 iris pigmentation, 469 INDEX 827

Prosimians, nocturnal, 604 Pterocera lamhis, 198 optic axis, 688 ocelli of, 142, 197 orbit, 498 Pterois, iris, 371 pupils, 472, 612 Pteromys. See Flying squirrel. tapetum cellulosum, 459 Pteropus. See Flying fox. See also Lemurs, Tarsier. Pterotrachea, accommodation in, 590 Prosobranchs, 196 eyes of, 199 neuro -secretory cells, 552 Pterygotus anglicus, 157 See also Buccinum, Patella, etc. eyes of, 157 Proteus anguinus, 334, 726 Ptychodera, kiminescence in, 740 eyes of, 727, 728 rhythmic, 22, 747 pineal organ, 714 Pufflnus puffiniis, 407 retina, 728 iris, 408 Protocerebrum, in arthropods, 521 navigation by, 63, 64 Protochordates, 227 retina, 417 eyes of, 227 sphincter muscle, 407 luminous organs, 740 Pulex irritans, 219 nervous system, 530 Pulmonates, 196 neuro -endocrine system, 552 eyes of, 197 See also Balanoglossus, Atnphio.vus, nervous system, 528 Ascidia. See also Helix, Limax, etc. Protopterus, 312 Pulvinar, 542 eyes of, 312 Pupil, characteristics in Prototheria. See Monotremes. anurans, 339 Protozoa, 179, 180, 510 birds, 408 bioluminescence in, 738 chelonians, 372 contraction in light, 7 chimferas, 290 eye-spots, 125 chondrosteans, 317 intercellular fibrils, 511, 512 crocodilians, 376 reproductive cycle of, 16 holosteans, 322 tropisms in, 570 lacertilians, 359 See also Amoeba, Euglena, etc. marsupials, 439 Protractor lentis muscle, in anurans, 336. yeoceratodus, 313 648 placentals, 470, 471, 613 in selachians, 285 selachians, 286 Protura, 217, 218 snakes, 388 eyes lacking in, 729 Sphenodon, 381 Psephurus, 315 teleosteans, 303, 304 urodeles, 347 Psettodes, 329 contractile, occurrence of, 612 migratory eyes in. 329 double, in Anableps, 324 Pseudocone eye, 167 in Leptognathus, 325 Pseudomoyias lucifera, luminescence of, stenopceic, 612, 641 738 Pupillary reactions, colour vision and, 621 Pseudoscorpions, 214, 215 consensual, 700 eyes of, 214 in amphibians. 339 Psocoptera, 218, 220 birds, 408 Psylla, reproductive cycle in, 17 cejahalopods, 146, 575 Ptarmigan (Lagopus mutus), coloiu" crocodilians, 376 changes in, 21 lacertilians, 361 Pieraspis, 234 placentals, 472 eyes of, 238 teleosts, 304 pineal organ of, 713 Purkinje shift, colour vision and, 622 828 INDEX

Purkinje shift, in birds, 629 Rabbit, Moll's glands lacking, 492 crocodilians, 628 movement, perception of, 705 fishes, 625 nictitating membrane, 493 frogs, 627, 628 ocular movements, 692 insects, 586 optic nerve -head, 488 Pycnogonida, 217 orbit, 497 Pygopus lepidopus, conus, 363 pectinate ligament, 464 fundus, 362 refraction of, 639 PyramidaUs muscle, in birds, 424 retina, 481, 484, 485 chelonians, 374 vascularization of, 477, 478, 480 crocodiUans, 378 urinary secretion, 560 Pyrophorus, luminescence in, 748 visual field, binocular, 673, 686, 687 Pyrosoma, luminescence in, 740, 745 vitreous, 476 Pyrrhula, ciliary venous sinvis, 408 Raccoon, 444, 445 lens, 409 colour vision of, 634 Python, ciliary venous sinvis, 386 fundus, PI. XIV

iris, 386 threshold to light, difference, 618 pupillary contraction, 388 Radiolaria, 179, 180 sclera, 385 luminescence in, 738, 748 molurus, fundus, 390 Radio -receptors, 116 regius, iris, PL IX Raja, 287 reticulatus, iris, PI. IX accommodation in, 647 See also Spilotes. colour changes in, 95 ramp -retina, 642, 643 batis, pupils, 287 Q clavata, 280 eye of, 275 Quadratus muscle. See Bursalis. pupils, 287 Quadrigeminal body, 534 miraletus, visual cells, 288 montagui, 280 Ramp-retina, 642, 643 R Rana, 334, 335, 342 area centralis, 344 Rabbit, 445 brain, 533 angle gamma of, 676 colour changes, 98 anterior chamber, 465 eye of, 334, 336 area centralis, 485 fundus, 341 blood supply to eye, 498, 499, 500 hue discrimination, 627 cerebral cortex, 543 pineal organ, 714 removal of, 545 pupils, 339 ciliary ganglion, 501 Purkinje shift, 628 region, 461, 462 visual cells, 342 colour blindness of, 633 cateshiana, iris, 337 conjunctiva, 491 pupils, 339 cornea, 453 clamata, phototaxis and temperature, epithelium of, 452 627 nerves of, 454, 455 esculenta, area centralis, 344 drainage channels, 473 iris, 337 gonadotrophic hormone, control of, 559 halecina, pupils, 339 iris vascularization, 468 pipiens, visual cells, 250, 344 lacrimal passages, 494 sphenocephala, iris, 371 lens capsule, 653 temporaria, fundus, PI. Ill sutures, 474, 475 iris, PI. Ill INDEX 829

Rana temporaria Reptiles, colour changes in, rhythmic, 20 migration of retinal pigment, 614, 615 colour vision of, 628 pupillary contraction, 340 diurnal, 603

retina, 343 eyes of, 353 ff. triple cones, 308, 342 degenerate, 731 visual cells, 344 median, 715, 716 Ranatra, telotaxis in, 56 fore-brain, 543 Ranzania truncata, eyes of, 273 removal of, 545 Rat, 445 lateral geniculate body, 541 blood supply to eye, 498 median eyes, 715, 716 colour blindness of, 633 mid-brain, 535 cornea, 453 migration of retinal pigment, 614 epithelium of, 452 of visual cells, 616 distance, judgment of, 704 movement, perception of, 705 eye of, 605 neuro -endocrine system, 557 lacrimal passages, 494 nocturnal, 603 Moll's glands lacking, 492 ocular movements of, 694 neuro -secretory cells, 551 optic thalamvis, 540 ocular movements, 696 primitive, 234, 235 optic axis, 688 pupillary reactions, 700 retina, rod-rich, 610 refraction of, 639 threshold to light, difference, 618 reproductive cycle in, 17 visual acuity, 663, 665 control of, 559 cells, 483 spatial judgments of, 702 Ratita-, 397 tectum, 535 annular pad, 409 telencephalon, 543 pecten, 411, 413 vision of, 599 See also Apteryx, Struihio, etc. visual acuity of, 661 Rattlesnake. See Crotalus. field, binocular, 682 Rattus. See Rat. pathways, 538, 544 Raven, 402 Respiration rate and colour vision, 623, eye, shape of, 402 625 See also Corvidae. Rete of Hiirlimann, 500 Ray. See Raja. Retina, characteristics in Reflexes, conditioned. See Conditioned Anableps, 325 reflexes, anurans, 341, 343 pvipillary. See Pupillary reactions. birds, 418, 419 Refraction of vertebrates, 638 cei^halopods, 145 amphibians, 638 chelonians, 372, 373 birds, 639 chimseras, 290 cyclostomes, 638 chondrosteans, 318 fishes, 638 crocodilians, 377 mammals, 639 dipnoans, 313 reptiles, 639 holosteans, 322 Reptiles, 353 invertebrates. See Retinule, Visual accommodation in, 648, 649 cells, etc. brain, 533 lacertilians, 361, 363 transection of, 534 lamjarey, 268 cerebral cortex, 543 Latinieria, 315 ciliary ganglion, 501 marsupials, 439 colour changes in, 82 monotremes, 435, 436 control of, 98, 558 placentals, 482, 483, 484 mechanism of, 87 Pterocera, 142 830 INDEX

Retina, characteristics in Retractor bulbi, characteristics in selachians, 287, 288 anurans, 345 snakes, 389, 390, 392 chelonians, 374 Sphenodon, 381, 383 lacertilians, 366, 368 teleosts, 304, 306 marsupials, 441 tubular eyes, 323 monotremes, 437 urodeles, 347, 348 placentals, 495, 496, 501 vertebrates, 248, 249 Sphenodon, 383 embryology of, 239 abnormal, in man, 497 anangiotic, 480 bursalis muscle, in lacertilians, 368 central artery of, 477 Rhabdites, 128 converse, 146 Rhabdome, 141, 158 corrugated, 642, 643 Rhacophorus leucomystax, iris, PI. Ill diurnal eyes, in. 610, 611 Rhamdia, eyes of, 725 duplicated, in tubular eyes, 323, 643 Rhea, 397, 410 holangiotie, 479 fundus, 410 inverse, 146 pecten, 413 inverted, 146 Rheotaxis, 73 in arachnids, 149 Rhineura floridana, degenerate eyes of, 733 molluscs, 147 Rhinoceros, 444, 446 vertebrates, 241 cornea, 453 merangiotic, 479 eyes of, 450 nocturnal eyes, in, 609, 610 fundus, PI. XV pavirangiotic, 480 nictitating membrane, 492 photo -inechanical changes in, 614 optic axis, 688 pure-cone, 611 pupils, 472 in Calamoichthys, 320 retinal vascularization, 480 colubrid snakes, 392 retractor bulbi, 496 geckos, 365 sclera, 450 Sciuridse, 483 Rhinoglena, frontal eye of, 194 pure -rod, 610 Rhinophis, eyelids, 393 in chimseras, 290 eyes, degenerate, 731 deep-sea teleosts, 305 Rhipidistia, 234, 235 echidna, 436 Rhizopods, 180 Lep idosiren ,313 contraction to light, 7 nocturnal geckos, 364, 365 See also Amceba, etc. placentals, 482, 610 Rhodopsin, 122 selachians, 288 Rhombencephalon. See Hind-brain. ramp-, 642, 643 Rhynchocephalians, 353, 379 rod -rich, 610 eyes of, 380 See also Sphenodon. structure of, and accommodation, 656 Rhythm, diurnal. See Photoperiodism. summation in, 611, 659 tidal, in crustaceans, 15' vascularization of, in vertebrates, 476, molluscs, 15 477, 478, 482 protozoa, 16 verted, 241 146, Rhytina, 446 See also Visual cells. Roach. See Rutilus. Retinal mosaic, perception of movement Robin. See Erithacus. and, 705 American. See Turdus migratorius. visual acuity and, 656 Rochon-Duvigneaud, Andre-Jean- pigment. See Pigment, retinal. Fran9ois, 332, 333 Retinella, 129 Rodents, 445 Retinule, 157 accommodation in, 653

1 INDEX 831

Rodents, area centralis, 485 Riitilus, double cones in, 308 blood supply to eye, 498 membrana vasculosa, 299, 300 chiasma, 487 ciliary muscle, 461 processes. 466 S region, 460, 462 colour vision in. 633 Saccopharynx, degenerate eyes in. 724 cornea, 453 Sacculina, 208 diurnal, 604 eyes lacking in adult. 734 lacrimal duct, 493 Sagitta, 194 lens, 606 ocelli of. 194 Moll's glands lacking, 492 Saki, 443 nictitating membrane, 493 Salamanders, 346 occipital cortex, removal of, 545 eyes of, 346 ocular movements in, 696 degenerate, 726 optic axis, 688 larvsp, colour changes in, 20 orbit, 497 control of, 558 pectinate ligament, 464 See also Axolotl. pupils, 470, 471, 472 See also Urodeles, Anihystoma, reactions of, 700 Salamandra. refraction of, 639 Salamandra, 346 retinal vascularization. 479. 480, 481 colour vision of, 628 retractor bulbi, 495 retina, 347 tapetum fibrosum, 458, 609 maculosa, fimdus, PI. IV vision of, 601 iris, 347 visual field, binocular, 687 Salmo salar. iris. PI. II zonular fibres, 475 trutta, SOS See also irtrious species (Rat. Squirrel, choroidal gland, 297 etc.). chromatophores, 88 Rods, in invertebrate retina, 128 eye of, 276, 293 in vertebrate retina, 250 pineal apparatus, 714, 715 development from cones, 252 retina, 306 differentiation from cones, 251 triple cones, 308 double, 253 visual field, binocular, 679 green (Schwalbe"s). inanurans, 342, Salmonidne, cornea, 294 344 double cones, 308 violet, in anurans, 342 eyelids, 312 in urodeles. 349 scleral cartilage, 292 See also Visual cells. Salpa, eyes of, 228 Rorcjual. See Whale, blue. Salticus, 214 Rotifera, 194 ocellus of, 140 cerebral eye of, 194 scenicus, eyes of, 213 dermal sensitivity of. 32. 114 Sandalops, 203 frontal eye of, 194 stalked eyes of, 203 Rudimentary eyes, 721 Sapphirina, eyes of, 209 in Limulus, 163, 212, 552 Sarcodina. See Rhizopods. Rviminants, 446 Sarcophaga, 58 area centralis, 485 cornea, transi^arency of, 584 cornea. 453 nervous system, 522 corpora nigra. 470 orientation to polarized light. 582 hyaloid artery, 481 telotaxis in, 57 pupils, 472 Sarcophilus. See Tasmanian devil. See also Sheep, Cattle. Deer, etc. Sarcoptes scabiei, 216 832 INDEX

Sarsia, 139, 182, Sclera, characteristics in ocellus of, 139 holosteans, 321 Saturnia pernyi, development of eye, 156 lacertilians, 356 Sauropsida. See Reptiles and Birds. lamprey, 265 Saw-fly, 220, 223 Lati?neria, 315 larvae, ocelli of, 141, 223 marsupials, 438 See also Neodiprion. monotremes, 433 Saxicola, 417 placentals, 450 infula in, 417 selachians, 281 Scallop. See Pecten. snakes, 385 Scalops aquaticus, degenerate eyes in, 733 Sphenodon, 380 Scaphiopus, pupils, 339 teleosts, 292 Scaphirhynchus, 315 Scleral cartilage. See Cartilage. pupils, 317 ossicles. See Ossicles. Scaphopods, 196 Scolopendra rnorsitans, 210 neuro -secretory cells, 552 Scombridse, adipose lids in, 311 sense organs, 197 See also Thunnus. Sceloporus, retinal pigment in, 361 Scopelarchus analis, tubular eyes of, 323 Schistocerca gregaria, dorsal light reaction Scorpcena, 302 in, 74 fundus, 306 ommochromes in, 123 tensor choroidese, 302 Schistosoma, 187 twin cones, 308 Schizopods, eyes of, 160, 591 Scorpion, 211 See also Stylocheiron, Mysids. ocellus, lateral, 140, 141, 211 Schlemm, canal of, 473 median, 150, 212 Sciuridse, 445 pseudo-. See Pseudoscorpions. accommodation in, 653 whip-. See Whip-scorpions. area centralis, 485 Scotocytes, 251 choroid, 457 Scototaxis, 31, 60 ciliary region, 460 Scutigera, 160 colour vision in, 633 eyes of, 160, 210 diurnality of, 604 Scylliorhinus, 287 lens, 474 ciliary papilla, 284 ocular movements of, 696 optic pedicle, 290 optic axis, 688 pvipils, 286, 287 disc, 686 canicula, 280 refraction of, 639 Scyllium. accommodation in, 647 retina, 485 blinded, behaviour of, 598 pure -cone, 612 colour changes in, 95 vascularization of, 479 Scymnus, brain, 533 vision of, 601 Scyphozoa, 182 visual acuity of, 663 See also Jellyfish. cells, 483 Sea-anemones, 182 field, binocular, 689 nerve fibrils in, 514 Sciuromorpha, 445 nervous responses, 515, 516 Sciurus vulgaris. See Squirrel, common. phototactie reactions of, 571 Sclera, characteristics in See also Actinia. amphibians, 334 Sea-cows. See Sirenians. birds, 403 Sea-cucumbers, 184 chelonians, 369 sensitivity of, 184 chimseras, 290 See also Holothuria. chondrosteans, 317 Seagulls. See Laridae. dipnoans, 313 Seal, 445 INDEX 833

Seal, bearded, pupils, 470, 472 Sensitivity to light, in insects, 584 common, 502 in vertebrates, 602 fundus, PI. XIV absolute, 616 harp, eye of, 447 binocular, 680 See also Phocida?, Pinnipedes. dermal, 113 Sea-lilies, 184 Sepia, 201 Sea-lion, 444, 445 colour changes in, 85, 92 pujDils, 470 conditioning of, 576 See also Pinnipedes. eyes of, 145, 202 Sea-spiders, 217 reactions of, 528 vision of, eyes of, 149, 217 576, 577 Seps, transverse muscle in, 357 Sea-squirts, 228 Sergestes prehensilis, photophore of, See also Ascidia. 746 Serpentarius cristatus, 413 Sea-urchins, 184 pecten, 413 sensitivity of, 185 Serranus, fovea, 309, 310 See also Diadema. ocular movements, 693 Secretary bird. See Serpentarius. cabrilla, 693 Sedentaria, 190 accommodation of, 645 Sedentary habit, degenerate eyes due to, optic nerve, 310 722 Sertularia hj^droid, pigment in, 120 Selache maximiis, 283 Sexual cycle in animals, 16 extra-ocular muscles, 290 control of, in crustaceans, 555 pupils, 287 in insects, 556 Selachians, 235, 278 vertebrates, 559 accommodation in, 647 Shadow-reflex, 45, 572, 574 brain, 533 Shearwater. See Puffmus. central nervous sj'stem, 532 Sheep (Ovis), 446 ciliary ganglion, 501 angle gamma, 677 colour changes in, 95 area centralis, 485 control of, 558 blood supjDly to eye, 499, 500 vision in, 624 corpora nigra, 470 electric organs in, 751 harderian gland, 494 eyes of, 279 if., 282 lens capsule, 653 degenerate, 724 optic axis, 688 labyrinths, 534 orbit, 498 luminous organs in, 741 pectinate ligament, 464 nocturnality of, 603 photoperiodism in, 18 palseocortex, 543 pupillary reactions, 472 pineal apparatus, 713, 714 retractor bulbi, 496 pupillary reactions, 612 vitreous, 476 consensual, 700 Shell-eyes, in Chiton, 196 refraction of, 638 Shock-reaction, 510 retina, pure-rod, 610 Shrew, 441 secretory mechanism, 267 elephant, 441 summation, retinal, 660 otter, 441, 443 tapetum, retinal, 612 tree-, 441, 442 threshold to light, absolute, 616 diurnality of, 604 vision of, 598 lens, 474 visual field, binocular, 679 true, 441 Seniotilus, colour preference in, 624 ciliary region, 460, 467 hue-discrimination, 626 eyes of, 449 threshold to light, difference, 617 retina, pure-rod, 610

S.O.—VOL. I. 53 834 INDEX

Shrew, visual cells, 482 Slugs, eyes of, 197 Shrike. See Lanius. vision of, 574 Shrimps, 206 See also Gastropods, Li?nax. eyes of, 163, 206 Smell. See Olfactory sense. luminescence in, 740, 743, 746 Snails, 196, 198 See also Crago, etc. conditioning of, 575 Sialia, fundus, 410, PL XII eyes of, 197 Sign-stimuli, in insects, 588 reproductive cycle in, 17 in vertebrates, 664 vision of, 574 Siluridae, blinded, dermal sensitivity in, See also Gastropods, Helix. 114 Snakes. See Ophidians. degenerate eyes in, 725 river-. ^See Homalopsinae. uveal tract, 299 sea-. See Hydrophinse. visual cells, rhythmic migration of, 19 tree-. See Dryophis, etc. See also Anieiurus. Snipe, visual field, binocular, 685 Simenchelys parasitica, 734 Soemmerring, D. W., 258, 259 eyes of, 735 Soleidfo, 328 Simians, 443 cornea, 296 See Anthropoidea. ocular movements of, 693 Simiidse, 443 scleral cartilage, 294 See also Apes, anthropoid. Solenogastres, 196 Simocephalus, conditioning of, 578 sense organs of, 197 Simple eyes, 129 Solenopsis, compound eyes of, 172, 225 composite, 152 Solifugaj, 216 ommatidial, 159 Sondermann, canals of, 473 Sinapsis alba (white inustard), helio- Souslik, 445 tropism in, 38 colovir vision in, 634 Sinus gland, in crustaceans, 552, 553 retina, 485 photoperiodic changes and, 19 Space, perception of, in insects, 589 Siphonops, eyes of, 730 in vertebrates, 666 Siren, eyes of, 349 Spadella, 194 Sirenians, 446 ocellus of, 135, 152, 194 lacrimal gland lacking, 493 Spalax, degenerate eyes of, 733 lens, 474 Spatial judgments, 700 ocular adnexa, 502 " Spectacle," primary, 265, 266 pupils, 472 in cyclostomes, 265 refraction of, 639 secondary, 255, 266 retinal vascularization, 480 in lizards, 366 retractor bulbi, 495, 496 snakes, 385, 392 visual acuity of, 654 teleosts, 312 Size, perception of, 667, 701 Spectral sensitivity of honey-bee, 585 Skunk [Mephitis), 445 Sphcerodactylus, fusion frequency in, 252 nictitating membrane absent, 493 argus, visual cells, 365' optic axis, 688 parkeri, visual cells, 252, 365 Sleep -movements in plants, 9, 10 Sphceroma lanceolata, 206 Sleep-rhythms in mammals, 13 Sphenisciformes. See Impennes. Sloth, 445 Spheniscus, visual field of, 685 2-toed, 445, 607 Sphenodon punctatus, 379 pupils, 612 accommodation in, 651 3-toed, 445 ciliary region, 380 Slow eyes, in insects, 584, 706 colour vision of, 628 Slow-worm. See Anguis. eyes of, 380 j^f. Slugs, 196, 197 fovea, 382, 659 INDEX 835

Sphenodon punctatus. Squalus fvmdus, PI. VIII chromatophores, 97 iris, 381 eye of, 275 parietal eye, 715, 716, 718 ptipils, 285, 287 function of, 719 Squatina, 288 pineal apparatus, 714, 715 pupil, 286 pupil, contractile, 612 visual cells, 288 retina, 382, 610 Squids, 196 visual acuity, 661 colour changes in, 85, 93 cells, 382 eyes of, 143, 202 Sphincter pupilla? muscle, characteristics in luininescence in, 740, 746 anurans, 337 See also Loligo. birds, 407 Squirrel, African, pupils, 472 lacertilians, 357 common, 445 monotremes, 436 colour vision of, 633 placentals, 468 pupils, 472 selachians, 285 retina, 484 snakes, 387 vascularization of, 479 Sphenodoti, 381 visual cells, 482 teleosteans, 303 flying. See Flying squirrel, Sphyrna tiburo, 327 ground. See Souslik. eyelids, 289 See also Sciuridse. eyes of, 327 Stalked eyes, in cephaloiDods, 203 zygcena, 327 in fishes, 326, 327 extra-ocular muscles, 327 insects, 223, 225 optic pedicle, 290 Starfish, 184, PI. I Spiders, 213 nervous system, 516 cave-. See Anthrobia. reactions of, 516 garden-. See Araneus. visual organs, 185 house-. See Tegenaria. See also Asterias. jumping, conditioning of, 580 Stargazer. See Astroscopus, Uranoscopus. vision of, 580 Starling, Ernest Henry, 548, 549 See also Evarcha, Salt ic us. (bird). See Lamprocolius, Sturnus. ocelli of, 139, 140, 149, 150, 213 Statocysts, in cephalopods, 202 ripple-, vibrotropism in, 579 in comb -jellies, 182 web -spinning, menotaxis in, 61 fishes, 74, 76 vibrotropism in, 579 scaphopods, 197 vision of, 579 tunicates, 228 See also Araneus, Tegenaria. Stato-kinetic reflexes, 667

wolf-. See Lycosa. Steatornis, iris, 407 Spilotes variegatus, head of, 384 Stemmata, 220, 222 Spinachia, colour preference in, 624 Stenopoeic pupils, 612 Spirographis, phototropic movements in, accommodation and, 641 39' Stenostonum, sense organs of, 189 Spondylus, 201 Stefitor, 179, 180 ocelli of, 148, 201 cceruleus, klmotaxis in, 49, 50 Sponges, 181 photosensitivity of, 125 myo -epithelial cells, 513, 514 Stephanoaetus, 606 reactions of, 513 See also Leucosoleiiia. Stereoscopic vision, 698, 700 Sporozoa, 180 Sterria hirundo, 419 Springtails. See Collembola. bifoveate retina, 419 Squalus, 97 Stick-insect. See Dixippus. 836 INDEX

Stickleback, visual acuity of, 660 Suoidea, 445 See also Gasterosteus, Eucalia, Spinachia. pupils, 472 Stigma, 125 tapetum lacking, 458, 609 Stizostedion, visual acuity of, 657 See also Pig, Hippopotamus, etc. visual cells, 307 Superposition eye, 169, 174 Stoneflies, 218 Supplementary layer of cornea, 296 Strepsiptera, 220, 221 Supi"a- oesophageal ganglion. See Streptopelia, 398, 681 Cerebral ganglion. Strigidse. See Owls. Supra-optic nucleus, 557 Stringops, 418 Suricate, 459 fovea, 418 diurnality of, 604 visual field, binocular, 685 pupils, 472 Strix aluco, anterior chamber, 404 tapetum lacking, 459, 609 fundus, 410, PI. XII Suspensory ligament, of iris, 464 head of, 402 of lens, in chondrosteans, 317 visibility of infra-red to, 630 in holosteans, 321 fiamtnea, pecten, 412 selachians, 285 Stroboscopic movement, 706 teleosts, 302 Strongylocentrotus, protection from light, urodeles, 347 39 See also Zonular fibres. .Struthio, 397, 405 Sutures (lens), in birds, 409 ciliary muscle, 406 in placentals, 474, 475 eye -shine, 405 selachians, 287 infula, 417 teleosts, 304 pecten, 411, 413 Swallow, bifoveate retina in, 418 Sturnus vulgaris, reproductive cycle in, 17 See also Hirundo. Stygicola, degenerate eyes in, 725 Swan, eye of, 399 Stylaria lacustris, ocellus of, 136 Sweat glands, conjunctival, 491 Stylocheiron, 160 Sycon, 181 eyes of, 160, 161 myo -epithelial cells, 513 luminous organ, 740 Synapta, sensitivity of, 184 Stylophorus, 322 Synchceta, cerebral eye of, 194 tubular eyes of, 324 Syngnathus, 309 Stylophthalmus paradoxus, 328 colour preference in, 624 eyes of, 327 fovea of, 309 Stylops, 221 visual field, binocular, 680 eyes of, 151, 221, 734 Syrnium. See Strix. Suboesophageal ganglion, in arthropods, 521, 522 Subscleral sinus, in lamprey, 266 Suctorians, 179, 180 Suidae, 445 Tabanidse, eyes of, 225 See also Pig. See also Tabanus, Ancala. Sula bassana, 407 Tabanus, 219 area centralis, 421 nervous system, 522 ciliary muscle, 407 Tachyglossus. See Echidna. distance, judgment of, 703 Tactile sense, 116 sphincter muscle, 407 colour changes and, 105 Summation, geniculate, 611 in crustaceans, 579 retinal, 611 Dytiscus, 104 visual acuity and, 659 fishes, 598 Sun-navigation. See Light-compass cave-, 726 reaction. insects, 581 INDEX 837

sense, in myriapods, 578 Tarsal glands, in mammals, 491 Tactile ' Pecten, 103 Tarsier, 442, 443, 613 spiders, 579 area centralis, 485 vertebrates, 597 eyes, shape of, 448 worms, 572 fovea, pure-rod, 486 spatial judgment and, 667 immobility of eyes, 696, 697 vibrissse, of camel, 492 pupils, 612, 613 of cat, 492, 601 retina, pure-rod, 482, 610 rodents, 601 threshold to light, 674 Taenia, 187 Tasmanian devil, 437, 438 Talitrus saltator, 61 fvmdus, PI. XIII luminous bacteria in, 738 tapetum fibrosum, 438, 609 menotaxis in. 61, 62 wolf, tapetum fibrosum, 438, 609 orientation to polarized light in, 73 Taste receptors, in bees, 588 time -memory in, 22 insects, 581 Talpa. See Mole. vertebrates, 534 Tapetal pigment, migration of, 19 Tauredophidium, degenerate eyes in, 724 Tapetum (lucidum), in compound eyes, Tautoga onitis, visual pigments in, 121 165, 168 Tealia, phototactic reactions of, 571 in crustaceans, 165 Tectum, 534, 690 insects, 168 in birds, 535 in simple eyes, 147 cyclostomes, 534 in arachnids, 149, 150 fishes, 534 crustaceans, 152 mammals, 536 molluscs, 148 Tegenaria domestica, 214 in vertebrate eyes, 606 ej-es of, 159, 213 cellulosum, 609 anterior median, 140 in placentals, 459 Tegmentum, 535, 690 choroidal, non-occlusible, 608 Telencephalon, 532, 542 in chondrosteans, 317 development of, 542 Latimeria, 315 Teleosteans, 235, 279 occkisible, 612 accommodation in, 645, 646 in selachians, 281 archicortex, 543 fibrosum, 609 blind, 724 in marsupials, 438 central nervous system, 532 placentals, 457 ciliary ganglion, 501 teleosts, 297 colour changes in, 84, 91, 96, 621 retinal, non-occlusible, 608 control of, 558 in chondrosteans, 318 pineal body and, 92 crocodilians, 377 vision in, 621, 624 deep-sea teleosts, 305 diurnality of, 603 Didelphys, 440 electric organs in, 751

Fteropus, 459 eyes of, 291 jg^., 293 occlusible, 612 degenerate, 724, 725, 735 in teleosts, 305 irides, PI. II Tapir, 444, 446 iris furrow, 337 optic axis, 688 lateral geniculate body, 541 retinal vascularization, 480 luminous organs, 741 Tarbophis, retinal vascularization, 301, migration of retinal pigment, 614 390 of visual cells, 614 visual cells, 392 neuro -secretory cells, 551 field, binocular, 684 olfaction in, 598 Tarentola, melanophores of, 87 pineal apparatus, 713 838 INDEX

Teleosteans, refraction of, 638 Threshold to light, absolute, in insects, secretory mechanism of, 267 584 tapetum, choroidal, 609 in vertebrates, 616 retinal, 612 binocular, 673 threshold to light, absolute, 616 difference, in insects, 585 difference, 617 in vertebrates, 617 vision of, 598 Thrips, 218, 220 visual acuity, 660 Thrush, 402 field, binocular, 679 shape of eye, 402 uniocular, 670, 672 Thunnus, 294 pathways, 536 scleral ossicles, 294 Telescope -eyed goldfish, 324 Thylacinus. See Tasmanian wolf. Telescopic eyes. See Tubular eyes. Thysanoptera, 218, 220 Telo-menotaxis, 61 Thysanura, 211, 218 Telotaxis, 31, 55 See also Lepisma. definition of, 43 Ticks, 216, 217 Temperature, diiirnal rhythm in, 13 eyes of, 216 Tenacular ligament, ciliary, in birds, 405 Tiger (Felis tigris), 445 in lacertilians, 357 area centralis, 485 orbital, in teleosts, 312 extra-ocular muscles, 495 Tenebrio larvae, photokinesis in, 114 pupils, 471 Tensor choroidese, in anurans, 335 Time -memory, in arthropods, 22 in birds, 406 in birds, 22 teleosts, 295, 302, 646 diurnal rhythm in, 22 Tentaculocysts, in jellyfish, 183 Tinamou, 397 Termites, 218, 729 Titmouse. See Parus. eyes lacking in, 729 Toad. See Bufo. See also Calotermes. clawed. See Xenopus. Terrapin, 374 fire-bellied. See Bomhinator. See also Clemmys, Chelonians, obstetric. See Alytes. Testudinidse, 369 Svirinam. See Pipa. Testudo, 369 Tomopteris, luminescence in, 745 ciliary musculature, 372 Topotaxis, 31 colour vision in, 629 Tornaria of Balanoglossus, 227 eye of, 370 Torpedo, 281 visual cells, 373 accommodation in, 647 field, binocular, 682 blinded, behaviour of, 598 Carolina, iris, 371 cornea, 281 grceca, scleral ossicles, 369 electric organ of, 751 Tetragonopterus, iris, PI. II pupil, 287 scleral cartilage, 294 Tortoise, 372 Tetraodon, fovea, 310 See also Che\onia,ns,, Testudo. Thalamus, optic, 538 Toucan, ocular inovements of, 696 Thalassarctos m-aritinius. See Bear, polar. Touch. See Tactile sense. Thallophytes (unicellular plants), 510 Toxotes jaculator, 701 Thaumatops magna, eyes of, 207 spatial judgments of, 701 Thelotornis, fovea, 388, 392 Tracheae, in compound eyes, 168 pupils, 388 Trachinus, fovea, 310 Therapsida, 234, 236 ocular movements, 693 Thermal sense of snakes, 599, 600, 667 Trachycephalus, pupils, 339 Thermo -receptors, 116 Trachysaurus, 682 Thermotropism, 33 visual field, binocular, 682 Thigmotropism, 33 Tragulina, 446 INDEX 839

Training techniques, 569 Tropidonotus tessellatus, accommodation, colour vision and, 624 649 Transversalis inuscle. in chelonians, 372 Tropo-menotaxis, 61, 68 in lacertilians, 357 Tropotaxis, 31, 52 pigeon, 407 definition of, 43 function of, 651 Trout. See Salmo trutta. Tree-frog. See Hyla. Trygon, 285 Tree-shrew, See Shrew, tree- iris, 285 Tree-snakes, accommodation in, 648 pupils, 287 fovea, 392 Trygonorhina, pupils, 286, 287 ocular movements of, 695 Trypanosoma, 179, 180 pupils, 388 Trypauchen, degenerate ej^es in, 726 visual acuity of, 661 Trypauchenophrys, degenerate eyes in, 726 field, 675 Tuatara. See Sphenodon. Trematodes, 187 Tuber nuclei of hypothalamus, 559 sense organs of, 189, 734 Tubular eyes, in cephalopods, 203 Triakis, pupil, 286 in fishes, 322, 323, 606 Tricheclnis. See Manatee. by artificial selection, 324 Trichomonads, 179, 180 optics of, 642, 643 Trichoptera, 219, 220 visual field of, 675, 680 Triclad worms, 187 Tubulidentata, 445 eyes of, 188 See also Aard-vark. See also Planarians, Dendrocoelum. Tunicates, 228 Trigla, visual field, binocular, 679 See also Ascidians. Trilobite, 157 Tunny. See Thunnus. eyes of, 157 Tupaia. See Shrew, tree. Trinoton aculeatum, eyes of, 221 Tupinamhis, ciliary region, 358

Triommatidion in aphids, 225 nigropunctatus , iris, PI V Triops. See Apus. Turbellarian worms, 187 Tristomum papillosurn, ocellus of, 130, 189 dermal sensitivity, 114 Tritocerebrum, in arthropods, 521 nerve-net, 516, 518 Tritiirits {Triton), 334, 346 nervous system, 518, 519 cartilaginous plaqvies, 347 sense organs, 188 colour vision in, 628 See also Planarians, etc. eyes of, 346, 728 Turdus migratorius, retinal summation in, iris vascularization, 347 660 retina, 347, 348 Tvirkey, nictitating membrane, 423 visual acuity of, 661 See also Meleagris. cristatus, 347 Turris, sense organs of, 183 colour changes in, 92 Tui-tle, 369 pyrrhogaster, iris, 347 See also Chelonians, Chrysemys, Emys, torosus, u-is, 347, 371, PI. IV etc. ^'' Troglichthys, degenerate eyes in, 726 Tylopoda, 446 Troihis, colour blindness of, 587 corpora nigra, 470 Tropidonotus fasciatus, optic disc, 390 pupils, 472 natrix natrix, 384 tapetum lacking, 458, 609 chiasma, 392 Typhlachirus, degenerate eyes in, 726 ciliary region, 388 Typldceontias, secondary spectacle, 367 colour training, 628 TypMias, degenerate eyes in, 725 pupils, 388 Typhlichthys, degenerate eyes in, 726 retina, 389 Typidocirolana, degenerate eyes in, 725 visual cells, 391 Typhlogobius californiensis, degenerate field, binocular, 684 eyes in, 726 840 INDEX

Typhlomolge, degenerate eyes in, 728 Ungulates, zonular fibres, 475 I Typhlonarke, degenerate eyes of, 279, 724 See also various genera. Typhlonectes, eyes of, 730 Uniocular vision, 697 Typhlonus, degenerate eyes of, 724 visual fields, 669 Typhloperipatus, degenerate eyes in, 724 Uranoscopus, pupil, 329 Typhlopidse, 383 visual field, binocular, 680 eyes of, 731 Urinary output, diurnal rhythm in, 13 Typhlops, eye of, 731 Urochordates. See Tunicates, Typhlotriton, degenerate eyes in, 728 Urodeles, 334 accommodation in, 648 colour vision in, 628 U eyes of, MQff., PL IV degenerate, 726 Uca, colour changes in, 95 lateral lines, 534 metabolic rhythm in, 16 migration of retinal pigment, 614 retinal pigment migration in, 19, 20 of visual cells, 616 Ultra-violet light, visibility of, in insects, ocular movements in, 694 585, 587 pineal organ, 714 in stickleback, 619 refraction of, 639 Umbra, colour vision in, 625 vision of, 599 threshold to light, difference, 617 Uromacer, visual field, binocular, 684 Umbraculum, pupillary, 470, 612 Ursidae. See Bears. Ungulates, 446 Uveal tract, characteristics in accommodation lacking in, 653 amphibians, 335 area centralis, 485 birds, 404 arhythmicity of, 604 chelonians, 370 blood supply to eye, 500 coelacanth, 315 ciliary muscle, 461 dipnoans, 313 processes, 466 fishes, 277 region, 461, 462 lacertilians, 356 circle of Hovius, 472 lamprey, 266 colour blindness of, 634 marsupials, 438 cornea, 453 placentals, 457 corpora nigra, 469 selachians, 281 Moll's glands, 492 snakes, 385 nictitating membrane, 493, 496 Sphenodon, 380 ocular movements of, 696 teleosts, 296 optic axis, 688 See also Choroid, Ciliary region. Iris. disc, 486 orbit, 498 pectinate ligament, 464 pupils, 471 V reactions of, 472 Vampire bat, 443 ramp -retina, 643 Vanadis, eye of, 143 refraction, 639 Vanessa, 170 retinal vascularization, 479 colour vision in, 587 retractor bulbi, 495 scototaxis in, 56, 60 spatial judgments, 704 vision of, 585 tapetum fibrosum, 457, 609 Varanus, conus, 362 vision of, 601 eye of, 354 visual acuity of, 664 orbit, 368 field, binocular, 689 visual field, binocular, 682 uniocular, 672 bengalensis, iris furrow, 337 INDEX 841

Vascular system of eye. See Blood supi:)ly Viperidse, visual cells, 392 to eye. Vision, central organization of, 509 Vena media, of anurans, 342 hormonal, 547 Ventral light reaction, 75 nervous, 511 Vemis mercenaria, metabolic rhythm in, 15 colour. See Colour vision, Vermilia infundibulum, ocelli of, 192 form. See Form vision, Visual acuity, Vertebrates, accommodation in, 640 genesis of, 102 ancestry of. 233 imaginative, 753 angle gamma in, 676, 677 of invertebrates, 570 brain of, 531, 533 arachnids, 579 central nervous system, 530 arthropods, 577 development of, 531, 532 irisects, 581

eyes of, 259 ff. molluscs, 574 adaptations of, 254 cephalopod, 575 degenerate, 723, 725, 730, 734 worms, 572 embryology of, 239 of vertebrates, 597 evolution of, 233 binocular, 697 ontogeny of, 239 uniocular, 697 origin of, 242 perceptual, 753 from Arnphioxus, 244 Visual acuity, of insects, 588 from Ascidian, 245 of vertebrates, 660 placode theory of, 246 amphibians, 661 phylogeny of, 237 birds, 662 structure of, 248, 254 fishes, 660 movement, perception of, in, 706 mammals, 663 neuro -endocrine system, 552, 556, 557 reptiles, 661 ocular movements in, 689 axis, 675, 676, 683 optic axis, 688 cells, 250 phylum of, 233, 234 characteristics in pineal apparatus, 711 invertebrates, 127, 128 refraction of, 638 apolar, 131 vision of, 597 bipolar, 130 colour, 619 See also Light-sensitive cells, form, 637 vertebrates, 250 visual acuity of, 660 anurans, 342, 344 fields, binocular, 672 birds, 419 uniocular, 669 chelonians, 372, 374 Vesicular eyes, 141 chondrosteans, 320 Vespa, 219 crocodiliaixs, 377 vision of, 584, 585 dipnoans. 313, 314 See also Wasps. holosteans, 321, 322 Vespertilio, 443 lacertilians, 363, 364 Vibratorj- receptors, 116, 534, 597 lamprey, 268, 269 in cetaceans, 601 Latimer ia, 315 fishes, 598 marsupials, 440, 441 snakes, 599, 667 monotremes, 436 Vibrotropism, in spiders, 579 Periophthalmus, 327 Viper, European. See Vipera berus. placentals, 482 horned, 392 selachians, 288 pit. See Crotalus, etc. snakes, 391, 392 Vipera berus, optic disc, 390 Sphenodon, 382 visual cells, 392 teleosts, 305, 307 Viperidse, facial pit in, 117, 599, 600 urodeles, 347, 348 842 INDEX

Visual cells, development of, 243 Vorticella, 179, 180 lengthening of, 643 Vulpes. See Fox. migration of, 614, 615 Vulture, African, visual acuity of, 662 rhythmic, 19 multiple, 253 W origin of, 252 centres, evolution of, 543 Walckenae7-a acuminata, eyes of, 214 in mid-brain, 534 Wallaby, 437, 440 fields, binocular, 672 ciliary region, 439 of amphibians, 682 eye of, 438 birds, 682, 684 Walls, Gordon, 352, 353 cyclostomes, 678 Walrus, 445 fishes, 678, 679 ocular adnexa, 501 mamiTials, 687, 689 pupils, 470 reptiles, 682 See also Pinnipedes. uniocular, 669, 670 " Warning colours ", 631 illusions, 703 Wasps, 219, 220 judgments, 700 digger-. See Philanthus. orientations, 669 eyes of, 160 pathways, cortical projection, 544 mnemotaxis in, 79 evolution of, 543 time-memory in, 22 in amphibians, 537 See also Vespa. arthropods, 524, 525, 526 Water-beetle. See Dytiscus. birds, 539 Water-fleas. See Cladocera. cephalopods, 528, 529 Weasel, 445, 472 cyclostomes, 535 pupils, 472 fishes, 536 Whale, beaked, ciliary receptor organs, 467 mammals, 540 blue, 444, 446 reptiles, 538 eyes of, 449 pigments, 118 hump-back, 444, 446 purple, 122 ciliary receptor organs, 467 trident, 684 sclera, 451 violet, 122 killer, 446 Vital spirits, 28 right-, 446 Vitamin A pigment system, 120 sperm-, 444, 446 in arthropods, 121 See also Cetaceans. molluscs, 120 Whelk. See Buccinum. vertebrates, 121 Whip-tailed scorpion, 214 Vitrellai, in compound eyes, 167 activity of, 34 Vitreous, characteristics in eyes of, 149, 150, 214 placentals, 476 Whirligig beetle, 74 selachians, 287 accommodation, static, 591 teleosteans, 304 orientation of, 74 Viverridse, 445 See also Dineutus. pupils, 470, 471, 472 Winteria, tubvilar eyes in, 324 retinal vascularization, 479 Wolf {Canis lupus), 445 Vizcacha, 442, 445 accommodation in, 653 pupils, 472 eye of, 447 Vole, field-, 445 nictitating membrane, 493 eye of, 450 optic disc, 486 red-backed, colour vision in, 633 Wolverine, pupils, 472 Volvox, 179, 180 Wombat, 437, 441 globator, klinotaxis in, 49 Wood, Casey Albert, 396, 397 INDEX 843

Woodlice, 206 Xerus. See Squirrel, African. eyes of, 206 Xiphias, 294 lacking, 729 dilatator muscle, 303 See also Annadillidiuni, Oniscus. optic nerve, 311 Woodpecker. See Dendrocopus, scleral ossicles, 294 Melanerpes. Xiphosura, 212 Worms, 186 neuro -endocrine system, 552 bilateral symmetry in, 186, 517 See also Limulus. bioluminescence in, 739, 745 X-organ, in crustaceans, 552, 553 eyes of, 187 in myriajDods, 552 nerve -net, 515, 518 nervous system, 518 receptor-effector system, 514 segmented. See Annelids. unsegmented, 187 phototactic reactions of, 572 See also Platyhelminthes, etc. Zaglossus. See Echidna. vision of, 572 Zamenis, visual field, binocular, 684 W-substance in amj^hibians, 97 Zebra (Equus zebra), 444, 446 corpora nigra, 469 See also Equidse. X Zeis's glands, in elejshant, 491 Zenaidura macroura, reproductive cycle in. Xanthophores, 88 18 in corneal epithelium of fishes, 295 Zenion, eyes of, 323 Xanthophyll, 119 Zonosaurus, eyelids, 367 in human macula, 122 Zonular fibres, characteristics in Xanthnsia, foveal pit, 365 anurans, 335 pupils, 359 birds, 410 visual cells, 252, 364 lacertilians, 361 Xenarthra, 445 monotremes, 436 cornea, keratinized, 456 placentals, 475 retinal vascularization, 480 selachians, 285 visual cells, 482 snakes, 389 Xenopus Icevis, 334, 337 Sphenodon, 381 colour changes in, 91, 98 See also Suspensory ligament. pineal organ and, 719 Zonurus giganteus, visual field, binocular, iris, 337 682 migration of pigment absent, 614 Zoraptera, 220 reproductive cycle in, 17 Zosterops japonica, reproductive cycle in, retina, 343 18