INDEX 



799 



Elaphe quadrivitatta, iris, 387, PI. IX 



quatorlineata, iris, 387, PI. IX 

 Elapidfe, iris, 386 



visual cells, 392 

 Elaps, pupil, 388 



Elasniobranchs. See Chondrichthyes. 

 Elaterid beetles, bioluininescence in, 736, 



740 

 Electric organs in fishes, 751 

 Electrophorus, electric organ of, 751 

 Electroretinograi^hic responses, and 



colour vision, 622 

 Eledone, 146 



eye of, 146 

 Elephants, 446 



African, 446 



cilia lacking in, 492 



eyelids, movements of, 491, 492 



eyes of, 450 



immobility of, 497, 696 



Indian, 446 



ciliary processes, 466 

 eye of, 447 



lacrimal passages lacking in, 494 



optic axis, 688 



orbit, 497 



retinal vascularization, 480 



sclera, 450 



tapetum fibrosum, 458, 609 



visual fields, 689 



Zeis's glands, 491 

 Elephas maximus. See Elephant, Indian. 

 Eliomys. See Dormouse. 

 Ellobius, degenerate eyes of, 733 

 Elysia viridis, menotaxis in, 61 

 Embioptera, 220 

 Ernplectonema kandai, bi(jluininescence 



in, 739, 746 

 Emu. See Dromceus. 

 Emyda, fovea, 374 



transparent eyelid, 374 



granosa, fundus, 372, PI. VII 

 Emys, scleral ossicles, 369 



orbicidaris, area centralis, 374 

 iris. PI. VII 

 Enchelioph is Jordan i, 735 

 eyes of, 735 

 pupils, 304, 612 

 sclera, 292 

 Engraulis, lids in, 311 

 Entosphenus, visual cells of, 269 

 Ephemeroptera, 218, 220 



accommodation, static, in, 591 



! Ephemeroptera, eyes of, 160 

 Ephestia, larva, tropotaxis in, 52, 53 

 Epicrates, lens, 389 

 Epinephelus, 92 



colour changes in, 92 

 Epiphysis. See Pineal organ. 

 Epomophorus, choroidal papilla?, 459 

 Eptatretus, degenerate eyes in, 734 

 Equidse, 446 



ciliary ganglion, 501 



cornea, 453 



corpora nigra, 469 



optic disc, 486 



pupil, 472 



See also Horse, Ass, Zebra. 

 Erax rufibarbis, telotaxis in, 56 

 Ereniias, transparent eyelids of, 366, 



367 

 Ericymba, visual cells of, 305 

 Erinaceus. See Hedgehog. 

 Eristalis, telotaxis in, 56 



tropotaxis in, 55 

 Erithacus, visual acuity of, 663 



visual responses of, 664 

 Ermine, colour changes in, 21 



pupil, 472 

 Errantia, 190 

 Erythrominatin, 123 

 Erythrophores, 88 

 Eryx, ciliary venous sinus, 386 

 Esocidse, cornea of, 294 

 Esox lucius, cornea of, 295 

 eye of, 275 



visual field, binocular, 679 

 Etmopterus, eyes of, 281 



pupil, 286 



threshold to light, absolute, 616 



visual cells, 288, 290, 611 

 Eucalia, threshold to light, difference, 617 

 Eucone eye, 167 



Eudendrium hydroid, phototropic 

 movements of, 39 

 jjigment in, 120 

 Eudyptes cristatus, 40S 



iris, 408, PI. XI 

 Euglena, 179, 180 



gracilis, eye-spot, 126 



virilis, eye-spot, 126 



klinotaxis in, 45, 48, 49 

 pigment in, 120 



inigration of, 85, 89 

 spectral sensitivity of, 120 

 Eunice, ocelli of, 191 



