702 



INDEX. 



Plasmodia of Myxomycetes, 519, 527; 

 chemistry of, 25 ; influence on move- 

 ment of, heat, 528; light, 528; solu- 

 tions, 529 



Plasmolysis (Fig. 9), 39, 44 



Plastic products, 138, 216; use of, 177 



Plastin, 25 



Pleurotsenium, phototaxis of, 525 



Poggioli, on heliotropic effect of rays of 

 different wave-length, 433 



Pohl, on movements of Mimosa, 535 



Poisoning of plants, 122 



Polar body, 640, 668 



Pollen-grain, 603 



Pollen-sac, 603 



Pollen-tube, 615 



Pollination, effect of, 626 



Pollinodium, 619 



Polyembryony, 627 



Polyphagus Euglena, phototaxis of, 524 



Polystigma, reproduction of, 623; life- 

 history of, 634 



Poppy, pendent position of heads, 455; 

 reversal of geotropic properties of, 459 



Porlieria hygrometrica, effect of drought 

 on movements of, 549 



Position, pendent, of flower-heads, 342, 

 455 



Potassium in food of plants (Fig 21), 

 132 



Potatoes, ash-analysis, by Herapath, 62 



Potency, relative of parents, 650; of 

 pollen, 648 



Potential energy, 288 



Pott, on formation of nitrogenous organic 

 substance in plants, 149 



Pouillet, on heat evolved in imbibition, 

 37 



Prantl, on growth of leaves, 381, 383, 

 395 



Prazmowski, on Clostridium butyricum, 

 292 



Pressure, effect of, on growth, 410 



Pressure, atmospheric, relation to plant- 

 life, 74 



Priestly 



on absorption, of carbon dioxide by 

 green plants, 8 1 ; of nitrogen by plants, 

 84; of oxygen by plants, 75; on 

 dephlogistication of air, 140 



Prillieux, on imperfect elasticity of 

 growing organs, 342 



Primary root, 419; shoot, 419 



Primordial cells, 2; utricle, 13, 23, 39; 

 osmotic properties of, 44 



Primula, glandular hairs of (Fig. 32), 

 245 ; heterostylism in, 647 



Pringsheim 



on chlorophyll-corpuscles (Fig. 22), 

 153 



Pringsheim 



on circulation of protoplasm, 524 

 on composition of chlorophyll, 154 

 on formation of cell-wall, 145 

 on hypochlorin, 147 

 on loss of colour by chlorophyll- 

 corpuscles when exposed to intense 

 light, 266 



on oil drops in Vaucheria sessilis, 146 

 on reproduction of Saprolegnieae, 

 620, 665 



on theory of function of chlorophyll, 

 157, 261 

 on xanthophyll, 241 



Procarpium, 614 



Proembryo of Characeae, 633 



Proembryonic branches of Chara, 599 



Promycelium, 634 



Pronucleus, male and female (Figs. 71, 

 75, 76), 617, 643 



Propagula of Floridese, 599 



Proper angle, 421 



Proteids, 24, 221; as reserve-materials, 

 171; formation of, 1 48 



Proterandrous and proterogynousflo wers, 

 647 



Prothallium, 629 



Protococcacese, reproduction of, 604 



Protococcus, i, 602 



Protomyces, conjugation of, 618; spores 

 of, 627 



Protonema, 629 



Protoplasm, 1,23; automatism of, 7, 301 ; 

 composition of, 24 ; conduction of 

 stimuli by, 374, 584 ; continuity of, 23, 

 374 (Fig. 64), 585; contractility of, 

 7 55 7, 568 ; decomposition of to form 

 starch, 145, 180, 217; difference be- 

 tween living and dead, 160; ecto- 

 plasm, 23 ; enchylema (Hanstein) 25; 

 endoplasm, 23 ; fermentative action of, 

 195 ; fundamental properties of, 6 ; 

 influence of light on motility of, 576; 

 irritability of, 7, 301, 371, 550; me- 

 taplasm, 23 ; microsomata, 23 ; mo- 

 tility of, 372, 408, 568; primordial 

 utricle, 23 ; reticulate structure of, 

 24; rotation of, 297,521 ; self-decom- 

 position of, 188, 204; streaming of, 

 5^i, 524 



Protoplasmic molecule, 160 



Pseudopodium, 516 



Puccinia Graminis, life-history of, 635 



Pugh, on absorption of nitrogen by 

 plants, 85, 126 



Pulsating vacuoles, 296, 522 



Pulvinus, 533; estimation of rigidity of, 

 560; mechanism of movements of, 

 561; of Mimosa pudica (Figs. 55, 

 56), 534 



