812 



INDEX 



Lepomis 



visual cells, 307 

 Leptinotarsa, 219 



metabolic rhythm in, 16 

 Leptodeira annulata, retina, 390 

 Leptodora, 207 



eyes of, 163, 209 

 Leptognathus, pupils, 304, 325 

 Leptoplana, 187 



activity of, 34, 572 

 Lepus. See Hare. 

 Leuckart's ratio, 401 

 Leucosolenia, 181 



light-sensitive cells in, 130, 181 

 Levator bulbi muscle, in anurans, 345 



palpebrae superioris, in placentals, 492 

 Lid-fold, in teleosts, 311 

 Lids. See Eyelids. 



Ligament. See Suspensory, Annular, etc. 

 Light, activation by, 7, 34 

 dermal sensitivity to, 113 

 diffuse reaction to, 113 

 effect on chromatophores, 89 

 metabolism, 7 

 movement, 27 

 pigmentation, 19, 82 

 inactivation by, 7, 34 

 perception of, 602 

 Light-compass reaction, 61 

 Light -differences, discrimination by in- 

 sects, 585 

 by vertebrates, 617 

 Light-sense, in vertebrates, 602 

 Light-sensitive cells, 127, 130 

 apolar, 128, 131, 133 

 bipolar, 127, 130, 134 

 in tail of ammocoetes, 263 

 Light-sensitivity, 102, 113 



in man, photoperiodism in, 559 

 Light-shadow reflex, 45 

 in molluscs, 574 

 in worms, 572, 573 

 Ligia, 95 



colour changes in, 95 



rhythmic, 20 

 eyes of, 165 

 Lima, eyes of, 139, 201, 722 

 Limax, 197 



maximus, visual cells of, 128 

 Limicoline habit, degenerate eyes due to, 



724 

 Limncea, 196 



nervous system, 528 



Limnesia, eyes of, 216 

 Limulus, 161, 211 

 activity of, 34 



eyes of, compoimd, 162, 212 

 mechanism of, 158 

 median, 141, 162, 212 

 rudimentary, 163, 212 



neuro -secretory cells in, 552 

 neuro-endocrine system, 552 

 orientation to polarized light in, 66 

 vision of, 584 

 visual pigments in, 121 

 Lineus ruber, 189 

 ocelli of, 189 

 orientation in, 75 

 Linnaeus, Carl, 8, 9 



flower-clock, 10 

 Lion (Felis leo), 445 

 angle gamma of, 677 

 area centralis, 485 

 cornea, 453 



extra-ocular muscles, 495 

 pupils, 471 



See also Felidae, Carnivores. 

 Lipophores, 88 



Liihohius, conditioning of, 578 

 Littorina neritoides, 45 

 phototaxis in, 45 

 Lizards. See Lacertilians. 

 Lizzia, 183 



ocellus of, 136 

 Llama {Lama), 444, 446 

 corpora nigra, 470 

 See also Tylopoda, Ungulates. 

 Local sign, 668 

 Localization in space, 666 

 egocentric, 668 

 gravitational, 669 

 Locusta, 69 



menotaxis in, 69 

 ommatidial angle in, 172 

 optic tracts, 526 

 vision of, 585 

 migratoria, ommochromes in, 123 

 optic ganglia, activity of, 524 

 telotaxis in, 56 

 Locusts, gregariousness in, 73 

 reactions of, 527 

 vision of, 583 



See also Locusta, Schistocerca. 

 Loeb, Jacques, 26, 28 

 Loligo, 145 



eyes of, 145, 202 



