236 INDEX 



Monkeys : colour vision, 68 ; sense 

 of taste, III, 113; sense of touch, 

 114, 120 



Mosaic vision, 23, 165 



Moths : HEARING : reception of 

 high frequency sounds, 180; 

 their counter to the sonar of 

 bats, 187; smell: organs for 

 detecting scent, 97 ; males de- 

 tect scent of females with 

 antennae, 97, 98, 201-2 



Movement of prey : importance of, 

 in feeding behaviour, 16, 17, 24, 

 27, 41 ; responses of lizards, 25, 

 51-3; responses of dragonflies, 

 34; responses of tree-frogs, 38; 

 in water, and responses of 

 turtles, terrapins, pond tor- 

 toises, 48 



Muscle sense, 218-19 



Mussels, eyes of, 158 



Mynahs, mimicry of, 82, 1 74-5 



Ommatidia (tubular cameras), 

 164-7 



Orang-outang, its sense of touch, 

 120 



Ostariophysi, and sonar, 191-2 



Ostrich, its eyelashes, 140 



Otocysts. See Statocysts 



Otters, their whiskers as tactile 

 organs, 209 



Ovipostors, of ichneumon flies, 1 18 



Owls : SIGHT : nocturnal and di- 

 urnal vision, 60-1 ; observations 

 and experiments on, 61-5; 

 optical mechanism, 148-9, 151; 

 alleged ability to detect infra- 

 red radiation, 216; hearing: 

 importance in hunting behav- 

 iour, 73; location of direction of 

 sound, 175, 176; structure of 

 ear, 175, 176 



Oyster-catchers, 135 



Oysters, eyes of, 157, 159 



Natterjack toad, 40-1 

 Nautilus, eye of, 158 

 Neck, short. See Short neck theory 

 Nerve cells : in sea-anemone, 1 28, 



131, 133; nature and function, 

 1 3 1-4; in Aurelia (jelly-fish), 

 133; receptor cells for smell, 

 196-7; receptor cells in taste- 

 bulbs, 204 



Nervous impulse, basically a 

 physico-chemical change, 131- 



132, 134 



Newts : scenting power, and ex- 

 periment on, 17, 102-3; voice- 

 lessness, 17, 72; field observa- 

 tions and experiments on its 

 sight, 43-6 ; sense of taste, 1 1 o ; 

 responsive to touch, 1 19 

 Nictitating membrane, 25, 139 

 Night-jars, their sense of touch, 



Nocturnal vision : of amphibians, 

 24 ; of mammals, 28-9, 84-5 ; of 

 owls, 60-1 



Norman, J. R., 181 



Oak Eggar Moth, 98 

 Ocelli (simple eyes), 23, 160-4 

 Octopuses: eyes of, 157, 158; their 

 gravity-receptorSj 221-2 



Pain, receptors for, 213-14 



Palmate Newt, 45 



Parrots : mimicry of, 82, 83 ; 



sense of smell, 92-3; sense of 



touch, 1 14-14, 119 

 Penguins, 142 



Perch, its scenting power, 91 

 Petrels, their sense of smell, 103, 



199 

 Pigeons, homing ability of, 226 

 Pike, scenting power of, 91 

 Pinnae. See External ears 

 Pit vipers : sense of touch, 115; 

 ability to detect infra-red radia- 

 tion, 215-16 

 Planarians, their limited sensory 



equipment, 15-16 

 Plumose anemone, 130 

 Poacher, as field naturalist, 106 

 Pointers, scenting powers of, 105 

 Pond tortoise, its response to move- 

 ment of prey in water, 48 

 Porpoise, its sense of smell, 1 98 

 Prawn, its response to differences 



in water pressure, 225 

 Proprioceptive senses, 218 ff". 

 Proprioceptors, of insects, 223 

 Protopathic sensation, receptors of, 



214 

 Protozoa, 125; limited sensory 



