314 
Promycelium, 89, Fig. 23. 
Pronuba, 257. 
Proteacez, 231. 
Protection against animals, 259, 260, 
261, 272, 295. 
Proterandry, 250, 251. 
Proterogyny, 250. 
Prothallium (see ‘“‘ Gametophyte’’). 
Protococcacer, 42, 43, 44, 45, 46, 47, 
48, 49, 50, 51, 57, 60, 76, 77, 78, 79, 
98, Fig. 7. 
Protococcus, 280. 
Protomyxa, 32. 
Protonema, 63, 114, 115, Fig. 29. 
Protophyte, Protophyta, 16, 37. 
Protoplasm, 3, 4, 22, 23, 61, 72. 
Psilotum, Psilotacez, 144, 147, 153. 
Pteridophyta, Pteridophytes (see 
also ‘‘Ferns’’), 16, 120, 122, 123, 
124, 125, 126, 128, 130, 132, 139, 143, 
144, 147, 148, 149, 152, 153, 156, 157, 
158, 159, 160, 161, 169, 172, 175, 176, 
184, 196, 223, 225, 268, 273, 290, 291, 
292, 293, 294; embryo of, 129, 130, 
181; fossil P., 154,'155; gameto- 
phyte, 123, 126, 127; heterospory, 
148; sexual organs, 128, 129; spo- 
rangium, 132; spores, 132; sporo- |- 
phyte, 123, 124, 130, 131. 
Pteris aquilina, 136. 
Puff-ball (Lycoperdon), 87, 90, 93, 94. 
Pyrenoid, 39, 59, Figs. 6, 13. 
Pyrenomycetes, 93. 
R 
Rafflesia, 279. 
Rag-weed (Ambrosia), 241. 
Rainfall (a factor in distribution), 
229, 237, 239. 
Ranunculus, Ranunculacee, 186, 207, 
208, 217, 246, 247, 270; R. aborti- 
vus, 246; R. Californicus, 246; 
R. Purshii, 270, Figs. 50, 59. 
Rattan-palm, 278. 
Ravenala, 193. 
Ray flowers (of Composite), 215, 
216. 
Receptacle, 207. 
INDEX 
Red Algz (Rhodophyces), 49, 63, 
70, 72, 73, 74, 78, 79, 99, 222, 263, 
295, Figs. 19, 20. 
Red-bud (Cercis), 212. 
Red cedar (Juniperus Virginiana), 
89, 90. 
Redwood (Sequoia sempervirens), 
174, 227. 
Reproduction, 3, 9, 25, 40, 41, 52, 55, 
58, 60, 62, 63, 65, 68, 69, 73, 78, 83, 
104, 105, 264, 285. 
Respiration, 8, 24, 25. 
Resting-spore (see also ‘‘ Odspore,”’ 
** Zygospore’’), 39, 41, 53, 54, 57, 
59, 60, 63, 264, 265; Chara, 63; 
Confervacee, 53, 54; fresh-water 
Alge, 264, 265; Fungi, 83, 85, 86; 
Vaucheria, 57; Volvox, 41. 
Resurrection-plant (Selaginella lepi- 
dophylla), 273. 
Rhaphides, 260. 
Rhizoids, 86, 107, 126. 
Rhizome, 193, 264, 282. 
Rhododendron, 214, 240. 
Rhodophycee (see also ‘Red Al- 
ge’’), 49, 70, 72, 73, 74, 75, 78, 79; 
color of, 71; continuity of proto- 
plasm, 71; fresh-water R., 73; re- 
production, 73, 74; Figs. 19, 20. 
Rhus (see ‘‘ Sumach’”’). 
Ribes speciosum, 249. 
Riccia, 103, 106, 109, 110, 111, 118, 
119, 122, Figs. 26, 27, 28, 33. 
Richardia, 246. 
Ricinus, 200, 209, Fig. 48. 
Rock-building Algz, 222. 
Rock-weed (Fucus), 69, 70, Fig. 18. 
Rocky Mountains, 232, 237. 
Root-hairs, 281. 
Roots, 21, 30, 67, 68, 69, 113, 120, 122, 
126, 129, 130, 131, 141, 144, 145, 162, 
170, 171, 172, 182, 183, 185, 189, 204, 
259, 267, 268, 276, 277; of Conifers, 
170, 171, 172; of Cycads, 162; of 
Dicotyledons, 189, 204; of Epi- 
phytes, 277; of Equisetum, 141; of 
Ferns, 122, 126, 127, 130, 131; Lyco- 
pods, 144, 145; Monocotyledons, 
183, 185, 268. 
