INDEX 



365 



Pisces, 235 



Placenta, 288 



Placoid scale, 232, 233 



Planaria, 16, 174 



Planesticus, 274 



Platyhelmia, 174 



Plecoptera, 71 



Pliny, 7 



Poisonous snakes, 263 



Polychaeta, 210 



Polymorphism, 72, 119, 165, 169, 172 



Polyp, 163, 165, 166, 170, 172 



Porcupine, 293 



Porifera, 157 



Primates, 293 



Proboscidia, 295 



Proglottid, 180 



Protective coloration, 84, 283 



Protein, 30 



Protoplasm, 28 



Prototheria, 289 



Protozoa, 134, 145 



Quaternary age, 336 



Rabbit, 292 



Radial symmetry, 17, 19 



Radula, 214, 217, 221 



Hat, 293 



Rays, 232 



Recapitulation Theory, 60 



Recognition colors, 91 



Redi, 26 



Redia, 179 



Regeneration, 53, 86, 159, 176, 196, 



200, 202, 206, 240, 248, 305 

 Rejuvenescence, 146 

 Reproduction, 36, 145, 150 

 Reptilia, 257, 266 

 Respiration, 67, 68, 82, 302 

 Retrogressive metamorphosis, 62, 



228 



Rhinocerus, 295 

 Rhopalocera, 103 

 Rhynchocephalia, 257 

 Rhynchophora, 116 

 Robin, 274 

 Rodentia, 292 



Rotifera, 188 

 Round-worms, 183 

 Ruminant, 295 



Salamanders, 250 



Salientia, 246, 251, 255 



Sarcodina, 135 



Sauria, 257, 261 



Saw-fly, 116 



Scale insects, 97 



Scallop, 223 



Scolex, 180 



Scorpion-fly, 102 



Scorpionida, 130 



Scyphozoa, 170 



Sea-cucumber, 201 



Sea-squirt, 226 



Sea-urchin, 200 



Seal, 292 



Sense organs, 79, 80, 205, 206, 244 



Serpentes, 257, 261 



Serricornia, 115 



Seta, 203 



Sharks, 232 



Ship worm, 219 



Shrew, 291 



Silkworm, 105 



Siphonaptera, 112 



Sirenia, 296 



Skeleton, 18, 19; vertebrate, 229 



Skink, 258 



Sleep, 303 



Sloth, 291 



Slug, 16 



Snail, 213 



Snake, 262 



Snake star, 199 



Snipe, 273 



Society, 320 



Soma, 140, 145, 148, 352 



Somatic variations, 351 



Songs, bird, 283 



Specialization, 47 



Spicules, 158 



Spider, 123, 124, 129 



Sponge fishery, 161 



Sponges, 157, 158, 169 



Spontaneous generation, 25 



