INDEX TO VOLUME X 
573 
Picea Abies, 506 
Pinus excelsa, ash content in leaves of, 379; 
radiata, 521; silvestris, secondary xylem 
of, 499; Strobus, cambium of, 501 
Piper Mestoni, 42 
Pisum, chromosomes of, 352 
Pittosporum, 532; crassifolium, tenuifolium, 
522; undulatum , 54 
Pivetta indica, 46 
Plagiochasma Rousselianum, archegonium 
of, 158 
Plagiochila, 530 
Platycerium alcicorne , 48; grande , 48 
Platylobium, 47 
Poa caespitosa, 526 
Podocarpus dacrydioides , 523; elata, 44; 
ferruginea, 519; to tar a, 519 
Podomitrium phyllanthus , 56 
Poitoea, 487 
Pollen- and seed- sterility in hybrids, 462 
Poly podium sp., 55, 519 
Polyporus shoraae , 133 
Polytrichum, 56 
Pomaderris, 521; elliptica , 54 
Potato, the formation and degeneration 
of germ cells in the, 325 
Potatoes, note on an indirect effect of 
spraying, with Bordeaux mixture, 113 
Potato-scab organism, 538 
Poihos Brownii , 42; longipes, 42 
Preissia commutata, archegonium of, 158 
Prunus americana, besseyi, domestica, nigra, 
self-sterility in, 476; pennsylvanica, 372; 
persica , experiments in ringing, 363; sero- 
tina, 506; triflora, self-sterility in, 476 
Pseudomorus Brunoniana, 46 
Pseudopanax lineare, 526; crassifolia, 530 
Psilotum, 41 
Psychotria luzoniensis, 506 
Pteridium aquilinum, 55, 552 
Pteris, 55 
Pterospermum niveum, 507 
Pterostylis, 54 
Puccinia coronata, 242; dispersa, 242; gram- 
inis, 242, 412, var. agrostis, 243, var. 
avenae, 243, var. phleipratensis, 243, var. 
secalis, 243, var. tritici, 242, var. tritici- 
compacti, 243; phleipratensis, 242 
Pyrus communis, experiments in ringing, 372 
Pythium debaryanum, 538 
Queensland and New South Wales. Aus¬ 
tralasian botanical notes I, 38 
Quercus alba, coccinea, rubra, 174 
Quince, fertility in, 476 
Quintinia acutifolia, 530 
Radula complanata, archegonium of, 158 
Rankin, E. J. (See W. E. Tottingham, 
203) 
Ranunculus Lyallii, 527 
Raoulia eximia, 528 
Raphanus, cambium of, 499 
Raspberry, fertility and sterility of, 474 
Ratonia tenax, 46 
Reboulia hemisphaerica, archegonium of, 158 
Reed, Guilford. The species concept 
from the point of view of a physiologist 
and bacteriologist, 234 
Renealmia, 510 
Reseda odorata, 468 
Resistance (to disease) induced by low soil 
moisture, experiments dealing with, 142 
Rhapidophora australasica, 42 
Rhipopogon scandens, 530 
Rhizoctonia on carnation, 134; severity in 
poorly drained lands, 133 
Rhizophora mucronata, 40 
Rhizopus, influence of temperature on the 
pectinase production of different species 
of, 127; pectinase in the spores of, 167; 
the relation of the enzym pectinase to in¬ 
fection of sweet potatoes by, 245; arrhi- 
zus, artocarpi, chinensis, delemar, maydis, 
microsporus, 127; nigricans, 127, 167, 
245; nodosus, oryzae, reflexus, 127; tritici, 
127, 167, 246 
Rhizopus nigricans and Rhizopus tritici, 
amylase in the spores of, 89 
Rhodamnia trinervia, 47 
Rhoeo, chromosomes of, 356 
Rhopalostylis Cheesemannii, 531; sapida, 174, 
519 
Riccardia pinguis, studies in the morphology 
of, 148; The chromosomes of, 170 
Riccia Bischojfli, natans, archegonia of, 158 
Ricinocarpus, 181 
Rigg, George B., Thomas G. Thompson, 
and William L. Gilliland. The in¬ 
fluence of plants on the air in houses, 383 
Robbins, William J. An isoelectric point 
for plant tissue and its significance, 412 
Robinia, 174; Pseudo-Acacia, meristems of, 
503 
Root hairs of wheat, the effect of the hydro¬ 
gen ion on the protoplasm of the, 211 
