798 



INDEX 



Dolichopteryx, tubular eyes in, 324 

 Dolphin, 444, 446 



cornea, 453 



keratinized, 456 



ocular adnexa, 502 



pineal body absent, 71 1 

 Dormouse, choroid, 457 



pupils, contractile, 612 



retinal vascularization, 482 



visual cells, 483 

 Dorsal light reaction, 74 

 Dorylus, 221 



eyes lacking in, 729 

 Dragon-fly, 74 



compound eyes of, 172, 222 



See also Anax, Aeschna. 

 Drainage channels in mammals, 472, 



473 

 Drepanophorus, ocellus of, 134 

 Driver ant, 221, 729 



eyes lacking in, 729 

 Droniceus, 397 

 Dromedary (Canielus dromedarius), 446 



See also Tylopoda. 

 Drosophila, 44 



colour vision of, 587 



dermal sensitivity in, 114 



electroretinographic responses, 586 



ommochroines in, 123 



optomotor reaction in, 583 



phototaxis in, 44, 45 



spectral sensitivity of, 585 



telotaxis in, 56 



time-memory in, 22 



vision of ocelli of, 582 



visual acuity of, 588 

 Dryophiops, pupils, 388 

 Dryophis, fovea, 388, 392 



pupils, 388, 674 



visual field, binocular, 682 

 Ducks, diving, accommodation in, 643 

 ciliary muscles, 407 

 nictitating membrane, 424 



gonadotrophic activities of, 18 

 nervous control of, 537, 560 



visual fields of, 685 



See also Dafila, Dendrocygna, etc. 

 Dugong, 446 



pineal organ absent, 711 



retinal vascularization, 480 

 Dytiscus marginalis, 168 



brain, 524 



eyes of, 168, 172 



Dytiscus inarginalis 



larva, dermal sensitivity in, 114 



ocelli of, 221 

 optic ganglion, activity of, 524 

 sensory reactions of, 103, 588 

 vision of, 584 



E 



Eagle, accommodation in, 651 



bald. See Haliaetus. 



bifoveate retina, 417, 418 



Chilean. See Geranoaetus. 



visual field, binocular, 684 

 Earthworm, 190 



bioluminescence in, 745 



eyes of, 190 



tropotaxis, 53 



visual cells, 131 



See also Lumbricus. 

 Eccentric cell in compound eyes, 158 

 Echidna, 430, 431 



ciliary processes, 433 

 body, 434 



eye of, 432 



fundus, PI. XIII 



optic axis, 688 



retina, 435 

 pure-rod, 610 



scleral cartilage, 433 

 Echinoderms, 183 



colour changes in, 82, 90 

 rhythmic, 20 



dermal sensitivity, 114 



luminescent, 739 



nerve-net, 515 



nervous system, 516 



origin of vertebrates through, 233 



phototactic reactions of, 571 



sense organs of, 184 

 Echinoidea, 184 

 Edentates, 445 



nictitating membrane, 493 



ocular movements of, 696 



optic axis, 688 



refraction of, 639 



vision of, 601 

 Eels, retina, 299, 301 



snipe-. See Borodinula. 



visual cells of, 307 



See also Anguilla. 

 Eiseniafmtida, conditioning of, 573 

 tropotaxis in, 53 



