478 



INDEX 



Plants, habit of, 264. 

 has problems to solve, 6, 29, 260. 

 how supplied with air, 176, 187*-190, 278, 



279,* 280,* 281,* 282-285. 

 injury of, 79,* 86,* 263. 

 land vs. water, 338, 339,* 340, 342. 

 length of life of, 286. 

 monocotyledonous, 135, 226. 248, 347. 

 monoecious, 302. 

 needs of, 6, 326. 

 poisonous, 222. 

 selective action of, 161. 

 strength of, how secured, 266, 267,* 268,* 



269, 270. 

 struggle of, for existence. See Struggle 



for existence. 



supply carbon dioxide to aQuaria, 285. 

 tendril bearing, 270-274. 

 twining, 275, 276. 

 water, characteristics of, 337,* 338,* 339,* 



340*-342. 

 weaving, 270. 



Plant-breeding, 331, 335, 409-411,* 412-413,* 

 414,* 415,* 416,* 417, 418,* 419,* 420-423,* 

 424,* 425,* 426,* 427,* 428, 429,* 430, 

 431*-444,* 445,* 446,* 447,* 448*, 449*- 

 453. 



Plant lice cause green flowers, 349. 

 Plantago. See Plantain. 

 Plantain, cross-pollination of, 303. 

 protection of pollen of, 295. 

 Rattlesnake, prefers coniferous humus, 



351. 



Water, 342. 

 Planting stick, 40.* 

 Plaster of Paris. See Lime sulphate. 

 Platinum wire, 366. 

 Plow sole, 126.* 

 Plowing, 126,* 127,* 128,* 132. 

 Plum, escape of, from seed, 54. 

 flower of, 431.* 

 improvement of, by breeding, 409-411,* 



412, 413,* 414,* 415,* 416,* 417. 

 pollination of, 430, 431.* 

 self -sterility of, 309. 

 See, also, Prune. 



Plum, American, 409, 410, 411,* 412, 413.* 

 Apple, 410. 

 Bartlett, 410. 



Plum, Beach, 410. 

 European, 409, 411. 

 Improved Beach, 412, 413,* 414.* 

 Japanese, 409, 410, 411. 

 Pond, 411. 



Stoneless, 415, 416,* 417. 

 Plumcot, 415.* 

 Plumule, 1,* 2,* 3 * 4* 



protection of, 71,* 72,* 79.* 

 Pneumonia, 380. 

 Pocket around caulicle, 20,* 58.* 

 Pod, 3. 



Poisonous plants, 222. 

 Pole Bean. See Bean, Pole. 

 Pollen, carried by insects, 289, 291, 297-311. 



wind, 300, 301, 310, 311. 

 effect of, 309, 311. 

 exclusion of, 289. 



germination of, 290,* 292, 293,* 294. 

 injured by rain, 294. 

 protection of, 294, 295. 

 use of, 289. 

 vitality of, 294. 

 Pollen-tube, 290,* 291 * 

 attracted by stigma. 293, 294. 

 grows away from air, 293. 

 Pollination, 289-311, 430-431,* 435, 436. 

 cross-, 301. 



effect on ovary, etc., 309. 

 self-, 301. 



Polygonatum. See Solomon's Seal. 

 Polygonum, protection of, against animals, 



223. 



Water-, 335,* 336,* 340.* 

 Pond Lily. See Lily, Water. 

 Pond Plum. See Plum, Pond. 

 Pondweed,"339. 

 Poor -man's -weather-glass, behavior of 



flowers of, 295, 296. 

 protection of pollen of, 295. 

 Pop corn, 7. 



Poplar, buds formed on roots of, 249. 

 cross-pollination of, 302. 

 flower-buds of, 286. 

 leaf of, hairy covering of, 213. 

 pollen of, carried by wind, 300. 

 preparation of, for flowering, 286. 

 protection of, against drying, 214. 

 water, 214. 



