1920] 



INDEX OF SUBJECTS. 



979 



Plants — Continued. 



behavior of organic substances in, 632. 



chlorophyll in, fate in autumn, 526. 



classilication by cell nuclei, 524. 



daily periodicity in, 820. 



distribution as affected by solar radia- 

 *tion, 731. 



drug, culture in Argentina, 746. 



drug, culture in France, 746. 



dune, ash of, 431. 



dye, culture in Nigeria, 637. 



effect of concentration of nutritive 

 media, 523. 



effect of phosphates on a-crotonlc acid 

 action, 131. 



fat production in, 430. 



fermentation of nectar, 730. 



fertility problems, 521. 



fiber. («ee Fiber.) 



flowering and fruiting as affected by 

 length of day, 819. 



flowering, dictionary of, 148. 



for feeding stuff.s in Germany, 170. 



for Nebra.ska, list, 240. 



freezing-point lowering, studies, 515. 



frozen, as affected by manner of thaw- 

 ing, 432. 



green, nitrogen fixation by, 430. 



green, phospho-organic salts in, 525. 



hardening, nature of, 643. 



heat production, 819. 



honey, American, 259. 



importation, rules and regulations, U.S. 

 D.A., 741. 



imported for trial, U.S.D.A., 635. 



inheritance of susceptibility to para- 

 sites, 841. 



iodin determination, 204. 



iodin in, 632. 



ionization of air by, 225. 



maritime, water economy of, 223. 



medicinal. (See Drug plants.) 



mucilage in, origin, 132. 



new forms due to half and mass muta- 

 tions, 222. 



nitrophile, around manure heaps, 430. 



oil seed, culture In Germany, 638. 



ornamental, culture experiments, Can., 

 741. 



ornamental, for Missouri, 838. 



ornamental, variety tests. Can., 741. 



oxalates in, 327, 730. 



perennial, for hardy border, 441. 



perennial, for Missouri, 838. 



perennial, old age in, 634. 



permeability. (See Permeability.) 



phenologlcal effect of bodies of water, 

 523. 



photosynthesis. (See Photosynthesis.) 



phylogenetlc studies, 818. 



phytochemical Investigations, 820. 



poisonous, 470, 471. 



poisonous, U.S.D.A., 470, 471. 



poisonous, of Canada, Can., 880. 



poisonous, of United States and Canada, 

 G49. 



Plants — Continued. 



poisonous, of Utah and Nevada, U.S. 

 D.A., 77. 



(See also Forage poisoning, and 

 apeciflo plants.) 



pollination. (See Pollination.) 



prairie, subterranean anatomy, 130. 



regeneration, quantitative laws in, 821. 



resistance to cold, 226. 



resistance to disinfectants, 822. 



respiration. (See Respiration.) 



response to wireless stimulation, 526. 



root cork in, ecological significance, 

 732. 



succession and distribution in Africa, 

 326. 



tendril tips, regeneration of, 525. 



toxic effect on one another, 29, 327. 



transpiration. (See Transpiration.) 



transplanting, fall v. spring. Mo., 141. 



twining, contact sensitivity, 525. 



variation. (See Variation.) 



vai'iegated, non-Mendelian inheritance 

 in, 433. 



variegation in, 433. 



vegetative points, studies, 130. 



•water as affected by light, 431. 



wild, uses, treatise, 649. 



woody. (See Woody plants.) 

 Phismodiophora hrassicm. (See Cabbage 



clubroot.) 

 Plasmodium — 



falfiparum, infection of Anopheles lud- 

 lovH with, 854. 



vivax, infection of Anopheles with, 55. 

 Plasmopara rlbicola spore.s as affected by 



cuprammonium washes, N.H., 44. 

 Plat experiments — 



heterogeneity as factor affecting yields, 

 526. 



probable error in, 527. 

 Plathypena scabra — 



notes, N.C., 450. 



on beans. Conn. State, 251. 



studies, 759. 

 Platyoaster spp., notes, 259. 

 Platynata sp., notes, 851. 

 Platypus compositus on sweet potatoes, 163. 

 Pleospora graminea, notes, 45. 

 Plestiothrips perplexus on corn, Conn. State, 



252. 

 Pleuropneumonia — 



bovine, diagnosis, 786. 



contagious bovine, control, 584. 



contagious, eradication, U.S.D.A., 471. 



(See also Pneumonia.) 

 Pleurotropia utahensis, parasitism by, U.S. 



D.A., 260. 

 Plowing, tractor. (See Tractor plowing.) 

 Plows — 



motor. In France, 289. 



tractor, light, design, 288. 

 Plum — 



brown rot, notes, 45, 349. 



diseases, control, III., 847. 



hog, durability tests of wood, 44. 



rust, notes, 45. 



