INDEX 
27 
References are to pages 
Petiole, of leaf. 
276 
Pitcher plant. 
289 
of clematis. 
289 
use of leaves in ... . 
366 
of nasturtium .... 
.288 
Pith in corn stem . . . . 
267 
Petroleum, formation of . 
340 
Placenta of flower . 
200 
Petunias, members of night- 
Plague of locusts 
30 
shade family .... 
301 
Plague, an epidemic disease 
514 
Phanerogams, a group of plants 
8 
Planarian worm 
175 
Pharynx, of earthworm . 
181 
Plantain, a weed . 
239 
of man. 
406 
Plant, biology. 
195 
Pheasant, a seed eater 
117 
breeding. 
388 
wings of. 
108 
conditions, change of . 
266 
Phlegmatic temperament, heart 
diseases . 
380 
tracing of. 
483 
ecology, defined . . . . 
374 
Phloem, discussed .... 
266 
food, of interest to farmer 
273 
conducting food materials 
269 
lice. 
32 
position in woody stem 
267 
members of Hemiptera . 
32 
position of, in vascular bundle 
266 
protected by ants 
53 
Phoebes, destroyers of Lepidop- 
life, mystery of ... 
378 
tera ....... 
43 
peculiarities of . . . 
366 
Phosphates. 
416 
or animal matter food 
of 
Phosphorus, a chemical element 
bacteria. 
310 
found in living things . 
13, 412 
Plant societies. 
369 
a poison. 
487 
Plant succession .... 
374 
in lipoid. 
480 
Plants as organisms, interest in 
378 
useful in body .... 
416 
Plasma. 
449 
Photosynthesis, defined . . 
278 
Plecoptera, order of insects . 
29 
finished product of . 
279 
Plerome of stem .... 
.247 
importance of .... 
279 
Pleurococcus, described . 
304 
oxygen produced by . 
279 
Plum, example of drupe . 
239 
performed by stem . . . 
371 
produced by rose family . 
298 
use made of products of . 
279 
Plumage, discussed . . . 
110 
vital process in plants . 
274, 
278 
Plumes on wind-distributed 
Phototropism. 
286 
seeds . 
241 
Phylloxera, injurious insect . 
531 
Plumule, connection with seed 
Physical change described . 
16 
leaves. 
221 
Physical training, value of . 
440 
defined. 
221 
Pieplant, storage of food in . 
252 
part of embryo .... 
221 
Pigment in skin .... 
459 
Pneumonia. 
449, 
489 
Pigs, important mammals . 
133 
Pod, form of fruit .... 
237 
Pike, a bony fish .... 
71 
Poison, defined. 
487 
raised in hatcheries . 
78 
in tobacco smoke 
485 
Pimples. 
504 
Poisonous character of crow- 
Pine, discussed . . . • 9, 
341- 
-344 
foot family. 
297 
tree, described .... 
341 
of lizards, Gila monster . 
101 
yellow, lumber of 
352 
of plants of nightshade family 
300 
Pinnately compound leaves 
of 
of snakes. 
101 
walnut family .... 
277 
of toxins. 
311 
Pistil, described. 
198 
Pollen, cell necessary for pro- 
Pistillate flower, described . 
204 
ducing seed . . . 
202, 209 
of monoecious plant . . 
204 
distributed by wind . . 
210 
Pitch, source of. 
346 
of pine. 
344 
