Index 



719 



Poliomyelitis, 210 



Polychaeta, 449, 450-454 



Polydactyly, 318 



Polydon, 569, 582, 589, 590 



Polyembryony, 520 



Polyergus, 534 



Polygordius, 449, 450 



Polymorphonuclear leucocytes, 178 



Polyorchis, 397 



Polyp, 383, 385, 391, 393, 395 



Polypide, 483 



Polypterini, 590 



Polypterus, 569, 582, 589, 590 



Polysaccharide, 31 



Polyzoa (see Bryozoa), 348, 482-484 



Pomoxis, 590 



Pond succession, 658 



Pons, 199, 200, 201 



Pool communities, 663 



Population, 667-669 



fluctations, 668 



growth, 667-668 

 Porcupine, 76, 91, 637 

 Porifera. 45, 346, 375-382, 645 



characteristics, 376-377 



classes, 381-382 

 Pork tapeworm (see Taenia solium), 



404, 417, 418 

 Porocephalus, 489 

 Porpoise, 628, 630, 637 

 Portal system, hepatic, 66, 168, 169, 

 415 

 renal, 66 

 Portuguese man-of-war (see Physa- 



lia), 393, 397 

 Postanal tail, 554, 566 

 Postcaval vein, 163, 168 

 Posterior chamber of eye, 217 



lobe of pituitary, 72, 243, 247-248 

 Potassium, 26, 29, 236, 269 



level in blood, 235 

 Potato beetle, 535 

 Poultry, 241 



inheritance in, 301, 305, 310-311 



parasites of, 432, 461 

 Prairie, 651, 654, 669 



dog, 630, 637 

 Prawn, 507 

 Praying mantis, 530 

 Preadaptation, 330 

 Precaval vein, 163, 168 

 Precocial bird. 621 

 Preen gland, 79 

 Preformation, 278 

 Pregnancy, 115, 182, 242, 247-248, 



263 

 Premaxilla. 57, 102, 103 

 Premolar, 87, 88, 130 

 Prepuce, 258 



Pressure, air, 155, 221 



blood, 174-175, 247 



diastolic, 175 



osmotic, 160, 186 



pulse, 175 



sense organ, 213 



systolic, 175 

 Prey, 130 



Priapulida, 347, 443, 445 

 Priapulus, 442 

 Primary oocyte, 275 



spermatocyte, 273 

 Primates, 44, 256, 263, 628, 630, 634- 



635, 641 

 Primitive streak, 284 

 Primordial germ cell, 273, 275, 287 

 Prismatic layer, 472 

 Pristis, 576, 580, 581 

 Proboscidea, 630, 639 

 Proboscis, of Acanthocephala, 443 



of Echiuroidea, 463 



of Enteropneusta, 556 



of Nemertina, 421, 422 

 Procavia, 630, 639 

 Procellariiformes, 625 

 Procercoid, 419 

 Process, 100 



acromion, 109 



inferior articular, 105, 106 



jugal, 103 



mastoid, 103 



odontoid, 106, 113 



olecranon, 109 



superior articular, 105, 106 



transverse, 105, 106, 107 



xiphoid, 108 

 Procyon, 630 

 Progesterone, 242, 263 

 Proglottids, 416 

 Prolactin, 246, 247, 262 

 Pronephros, 185 

 Pronghorn, 88 

 Pronotum, 522, 523 

 Pronucleus, 277 

 Prootic, 56 

 Prophase, 270-271 

 Prosopyle, 379 

 Prostate gland, 258 

 Prostatic fluid, 258 

 Prostomium, 450, 455 

 Protection, 100, 105. 107 



skeletal system, 92-93 



skin, 75-76 

 Protective coloration, 336 

 Proteidae, 596 

 Protein, 31-32, 145 



metabolism, 235 

 Proterozoic era, 343 

 Prothorax, 522 



