INDEX. 



Otter, 443 



Ovary, 69 



Oviduct, 248, 342, 402 



Ovipositor, 268 



Oviparous, 342 



Ovum, 28 



Owls, 416, 417 



Ox, 442 



Oxidation, 15, 61 



Oysters, 237, 254 



Palcemonetes, 291 



Palaeozoology, defined, 5 



Papilio, 301 



Papulae, 207 



Parapodia 219 



Parainecinm, 142, 146 



Parasitic worms, 199 



Parasitism, 123, 190, 193, 199 



Parental care, 108, 448 



Parthenogenesis, 108, 283 



Passeres. 422 



Pea-fowl, 413 



Pearls, 254 



Pearl oyster, 254 



Pecten, 254, 255 



Pelagic fauna, 129 



Pelecanus, 412 



Pelecypoda, 252 



Penguin, 411 



Pennaria, 177 



Perennibranchiata, 379 



Pericardial sinus, 279 



Perichondrium, 49 



Periosteum, 49 



Peripatus, 292 



Peripheral nervous system, 74 ; 344, 



348 (see nervous system) 

 Perissodactyla, 442 

 Peritoneum, 314 

 Periwinkles, 254 

 Perodipus, 444 

 Petrels, 412 

 Pharyngognathi, 369 

 Pharynx, 331 

 Pheasant, 413 

 Phcenicopterus, 411 

 Pholas, 253 

 Phyla, key to, 140 

 Physalia, 179 

 Physiology, defined, 4 

 Physostomi, 369 

 Picariae, 419 

 Pieris, 299 

 Pigeon, 416 

 Pigments, 10 

 Placenta, 438 

 Placentalia, 429, 440 



Planarians, 187 



Planorbis, 257 



Plant-lice, 296 



Planula, 176 



Plasma (blood), 52, 336 



Plastron, 388 



Platyhelminthes, 185 



Plectognathi, 369 



Pleura, 335 



Pleuron, 262 



Plexus, 348 



Plover, 412 



Plitmatella, 185, 196 



Polar bodies, 30, 31 



Polychaeta, 230 



Polygordius, 228 



Polymorphism, 180, 181 



Polyp, 170 



Polyzoa, 185, 195, 196 



Porcupine, 444, 445 



Porifera, 140, 156 



Porpoises, 441 



Potato-beetle, 302 



Prairie dog, 444 



Premolar (teeth), 433 



Primary vesicles (brain), 344 



Primates, 447 



Proboscidea, 443 



Proctodoeum, 60, 277, 330 



Proglottis (segment), 190, 191 



Promorphology defined, 3 ; illus- 

 trated,; 83 



Pronucleus female, 30; male, 31 



Prophase, 23 



Prostomium. 224 



Protective resemblance, 119 



Proteids, 10 



Prothorax, 269 



Protoplasm, 9 ; chemical composition 

 of, 10 ; physical structure, 10 ; physi- 

 ology, ii, 59; relation to life, 8 



Protopodite, 263 



Protopterus, 370 



Proto-vertebrata, 308 



Protozoa, 140, 142 



Proventriculus, 277, 400 



Pseudopodia, 147 



Ptarmigan, 414 



Pteropus, 446 



Pulp-cavity (see teeth) 



Pupa, 285 (see metamorphosis) 



Pyloric caeca, 277, 314 



Quadrate bone, 383, 432 



Quail, 413 



Quill (see feather) 



Rabbit, 444 



