378 



INDEX 



Pectase, 192 



Pedigree cultures, necessity of, 240 



hybrids, behavior of, 231 

 Perception, 19 

 Pericycle, 24 



in roots, 3 5 



topography of, 35 

 Periderm, 54 

 Phelloderm, 54 

 Phellogen, 27, 54 



in roots, 56 

 Phloem, 24 



as food carrier, i 59 



constitution of, 36 



parenchyma, 36, 158 



relation of , to other tissues, 162 



relation of one year's elements 

 to those of the next, 171 



secondary, 41 

 Photosynthesis, 140 



conditions affecting, 148 



in lower plants, i 50 

 Pine wood, cellular structure of, 



Fig- 52 

 course of water in, Figs. 53, 54, 



55. 5 6 

 Pith, 24 



development of, 41 

 Plasma, i 



membrane, description of, 3 



selective action of, 92 

 Plastids, 8 



Polariscope, use of, 282 

 Polar nuclei, 229 



Poplar, cross section of wood of, 81 

 Potassium myronate, 181 

 Primary cortex, 24, 30 



endosperm nucleus, 229 

 Primordial meristem, 24, 26 

 Primary permanent tissues, 27, 28 



vascular bundle, 36 

 Procambium, 24, 26 

 Protection by bast fibers, stone 

 cells and collenchyma, 72 



from injuries and loss of water, 



61 

 Protective tissues, diagram of, Fig. 



35 



Proteoly tic ferments, 192 

 Protoderm, 24, 26 

 Proteids, 181 

 Protoplasm, i 

 Protoplast, i 



description of, 2 



etymology of, i 



powers of, 1 7 

 Pyrus Japonica, epidermis of, Fig. 



Reagents, use of, 283 

 Recessive characters, 231 

 Reproduction, 213 

 Reserve cellulose, 179 

 Respiration, aerobic, 123 



anaerobic, 123 



Ring of annual growth, 51, no 

 relation of, to growth in length, 



112 



to the leaves, 113 

 Root, cross section of, 34 

 hairs, 90, 91 



diagram of, Fig. 42 

 excretions from, 93 

 parts of, Fig. 44 



Roots, growth in thickness of, 53 

 in the soil, 90 

 vascular bundles in, 53 

 Russian olive, epidermis of, Fig. 31 



Saccharose, 178 



Schizogenous intercellular spaces, 



202 



Sclerenchyma, 32 

 Secondary cortex, 55 



increase in thickness, 46 



meristems, 28 



permanent tissues, 28 



xylem and phloem, 41 

 Secreting cells and glands, 200 

 Secretions, nature of, 199 

 Secretion, process of, 208 

 Section cutting, 251 



with microtome, 2 53 



knife, care of, 2 55 

 Sections, kinds of, 253 

 Sexuality, significance of, 246 

 Sieve parenchyma, 3 7 



tubes, 36, i 58 

 contents of, 3 7 

 length of time active, 172 

 Silica, incrustations of, 63 

 Skeleton, making of, 76 



progressive development of, 

 Fig. 41 



in leaves, 86 



topography of, 83 

 Soil particles, Fig. 43 

 Solanin, 181 



Solutes, distribution of through 

 leaf, 114 



method of intake of, 94 

 Spermatophytes, spore-formation 



in, 221 



Sperm nuclei, 229 

 Spongy parenchyma, 145 

 Spore-formation, 216 

 Spores, germination of , 217 



