Index 887 



Polymorphism, 851 

 Polynesian region, 598 

 Polyneuritis, 474, 770,* 772 

 Polyp, 289,* 290 

 Polyploidy, 673, 676-680 

 Polypodium (fern), 138, 139,* 198 

 Polysaccharide, 87 



Polysiphonia, 119, 119,* 154, 164 (see 

 also Algae, red) 



Polytrichum, 133, 133,* 186 {see also 

 Moss) 



Pond scum, 157 



Pons, 54, 495,* 496,* 502, 504 



Porella, 131, 132,* 189 (see also Liver- 

 wort, Porella) 



Porifera (sponges), 279-286, 535, 536 



Pork worm, 539 g 



Porocyte, 283* 



Portuguese man-of-war, 289, 289* 



Postcaval vein, 315,* 480, 741* 



Potential energy, 105 



Pounce, 542 



Praying mantis, 554, 667* 



Prebus, 35 



Precipitin, 520 



Predacious (predatism), 635, 636, 658, 

 666, 667* 



Preformation, 842 

 Prenatal, 852 



Primary germ layers, 445,* 451-454 

 Primordial germ cells, 708-712, 708,* 

 710* 



Principle, barriers, 595 



cell, 37-45 



definite habitats, 594 



discontinuous distribution, 596 



dispersion, 593 



hibernation, 594 



highways, 595 



longitudinal distribution, 591-604 



migration, 591-604 



vertical distribution, 597 

 Proboscis, 326,* 327,* 369, 375,* 410* 

 Proctodeum, 447 (see also Embryology) 

 Progesterone {see Endocrine glands) 

 Progestin, 452 

 Proglottid, 293, 377, 377* 

 Prophase (mitosis), 62, 63,* 66* 

 Prophylaxis, 520 

 Propolis, 405 



Prosecretin {see Endocrine glands) 

 Prosopyle, 282,* 284* 

 Prostate, 513, 514, 514* 

 Prostomium, 307,* 384, 385,* 388* 

 Protective resemblance, 730, 760 

 Protein, 85, 88, 92, 476 

 Proterozoic era, 614, 617 

 Prothallus, 137,* 138, 138*, 188, 192, 

 193, 197 



Prothrombin, 486, 487 



Protococcus (pleurococcus) (green 



Alga), 115,* 116, 154, 157 

 Proton, 79,* 80, 81, 81,* 83* 

 Protonema, 134,* 187, 188 

 Protoplasm, 37-45, 73-103 



chemical properties, 84-92, 750 

 physical properties, 93-103, 750 

 Protoplasmic strands, 41, 42,* 362,* 



363 

 Protoplast, 44, 123,* 160 

 Protopodite, 320* 

 Protozoa, 274-279, 275*-280,* 344-367, 



530-535, 660 

 Protractor muscle, 312* 

 Proventriculus, 394 

 Psalliota (Agaricus) {see Mushroom) 

 Pseudopodia, 123, 172, 173, 188, 274, 



275,* 286,* 344, 345, 345,* 



346* 

 Pseudospora, 535 

 Psychology, 853 

 Psychrophile, 122, 170 

 Pteridium (Pteris), 138, 138,* 195-198 



{see also Fern) 

 Pteropsida, 110, 137, 138, 138,* 191, 



195, 200-205, 206-213 

 PtyaHn, 476 



Puccinia, 181-183, 182* 

 Pulmonary, 311,* 312,* 480,* 741* 

 Pulvillus, 394, 401,* 402 

 Punnet square, 686-690 

 Pupa, 399,* 407, 413,* 419 

 Pupil, 438, 497, 505 

 Pure line in heredity, 853 

 Putrefaction, 671 



Pycniospore, 129, 167, 181, 182, 182* 

 Pyloric, 302,* 321,* 332,* 426, 427,* 



473 

 Pyrenoid, 115, 115,* 117, 118, 153, 



155, 156, 156,* 157, 162, 



276,* 358,* 359 



Q 



Quarantine, 637 

 Queen, 399, 399,* 406 



R 



Race improvement, 526-527 

 Radial symmetry {see Symmetry) 

 Radicle, 210-213 

 Radioactive, 82 

 Radiolaria {see Protozoa) 

 Rafinesque, 802 

 Rana {see Frog) 

 Ranunculus {see Buttercup) 

 Ranvier, node of {see Nerve) 

 Raphe, 213 



