662 



INDEX 



Parasites, 215 



blood-inhabiting, 219 



digestive tract of, 219 



eggs of, 219 



external, 216, 219, 221 



indirectly acquired, 617-621 



internal, 216, 223 



maintenance of cycle, 220 



periodic, 216, 222 



permanent, 216, 223 



relationships of, 216 



reproductive capacity of, 219 



requiring one host, 223 



requiring more than two hosts, 229 



requiring two hosts, 225 



respiration of, 219 



temporary, 216, 221 

 Parasitic diseases, 634-635 

 Parasitic Hymenoptera, 221 

 Parasitic life, effects of, 218 

 Parasitic worms, harm caused by, 582 

 Parasitism 



as a biological adaptation, 492 



art of, 215 

 Parasympathetic, 354 

 Parathyroid, 396 



principle of, 402 

 Parenchyma, 245, 252 

 Park, Wm. H., 623 

 Parker, experiment with sea anemone, 



382 

 Parotid gland, 293 

 Parrots, 114, 488, 552 

 Pars intermedia, 402 

 Pars nervosa, 400, 402 

 Pars tuberalis, 400 

 Parthenogenesis, 413, 471 



in mammals, 413 

 Parthenogenetic agents, 413 

 Passeriformes, 114 

 Passive immunity, 632-634 

 Pasteur, 407, 631-632 

 Pasteur Institute, 632 

 Pathogens, 621 

 Pavlov, work of, 575-380 

 Peas, garden, 444, 445, 454, 459 



sweet, 451 

 Peccary, 508 

 Pectin, 244 



on bee's leg, £07, 208 

 Pectinatella, 91 

 Pectoral girdle, 332 

 Pedigree breeding, 453 

 Peking man, 565 

 Pelecypoda, 97 

 Pellicle, structure of, in Paramecium, 



158 

 Pelvic girdle, 331, 332 

 Pelvis (of kidney), 823 



Penguins, 113 

 Penn, William, 639 

 Pentacrinus, 95 

 Pentadactyl limb, 332 

 Pepsinogen, 294 

 Peptones, 294 

 Perching birds, 114 

 Perennial, 240 

 Period 



post glacial, 476 



recent, 476 



time, 475 

 Periosteum, 338 

 Peripatus, 99 

 Peripheral nervous system, earthworm, 



194 

 Perisarc, 185 

 Perissodactyla, 117 

 Peristalsis, 290, 291, 294 

 Peristome, moss, 176 

 Permian period, 476, 513 

 Perpetuation of species, 335 

 Persians, 561 

 Petals, 497 

 Petiole, 250-251 

 Petrifactions, 478 

 Petromyzon, 105 

 Pettenkofer, 312 

 Pettersson, 35 

 Peyer's patches, 292 

 Phaeophyceae, 71 

 Phagocytes, 626 

 Phalanges, 332 

 Pharyngeal tonsUs, 287 

 Pharynx, 287 



earthworm, 189 

 Phascolosoma, 93 

 Phenotype, 446, 449 

 Phillips, 438 

 Philodina, 89 



Phloem, 243, 246, £47, 248, 250 

 Phoenicians, 561 

 Phoronidea, 91 

 Phoronis, 91 

 Phosphorus, 277 

 Photoreceptors, 358, 359 

 Phycomycetes, 71 

 Phyla, 65 

 Phyllophora, 71 

 Phylogeny, 501 

 Physalia, 81 

 Pia mater, 345 

 Pig, 514, 515 

 Pigeons, 114, 335 

 Piltdown man, 556, 565 

 Pincus, 413 

 Pineal eye, 350 

 Pineal gland, 397, 398 

 Pines, 75 



