6i4 



Journal of A gricultural Research 



Vol. xvni 



Page 



Night, effect of length on growth and repro- 

 duction in plants 553-606 



Nitrate — 



absorption by plant 73-117 



ammonium, effect on yield in acid soils. 121-122 

 calcium — 

 effect of moisture in substratum on physi- 

 ological proportion to other salts 357-3 78 



toxic limits 272-274 



in soils at various moisture contents 141 



nitrogen in water-free composts 334-33 7 



potassium, toxic limits 272-274 



sodium — 

 effect on — 

 sodium-bicarbonate tolerance of wheat 



seedlings 353 



sodium-chlorid tolerance of wheat seed- 

 lings 352 



sodium-sulphate tolerance of wheat 



seedlings 353 



toxic limits 272-274 



Nitrates — 

 in acid soils, effect of carbonates of calcium 



and magnesium 122-124 



toxic limits 272-274 



Nitrification, effect of oxidation of sulphur. 329-345 



Nitrite nitrogen in water-free composts. . . . 334-337 



Nitrogen — 



absorption by plant 73-1 1 7 



in Hordeum. spp 55-72, 78-96 



in poultry feces 394 



in Sorghum xulgare 4-30 



nitrate, in water-free composts 334-33 7 



nitrite, in water-free composts 334-337 



Nitrogen Metabolism of Two- Year-Old Steers 

 (paper) 241-254 



Nitrogen-free extract — 



in brown and black alfalfa 301-303 



in Sorghum vulgare 4-30 



in sunflower and com silage 327 



in yellow-berry wheat 167 



Noctua c^igrum — 



at light traps 477-481 



host oi Sorosporella uzella 405,432-436 



Noctuid larvae, parasitized by Sorosporella 

 uvella 399-440 



Nonsugar solids in juice of Sorghum vulgare. . 16-22 



Noronhia emarginata, host fruit of Ceratitis 

 capitaia 442-446 



Notes on the Composition of the Sorghtun 

 Plant (paper) 1-31 



Notes on the European Com Borer (Pyrausta 

 nubilalis Hiibner) and Its Nearest Ameri- 

 can Allies, with Description of Larvae, 

 Pupae, and One New Species (paper). . . . 171-178 



Noyes, H. A., and Conner, S. D. (paper): 

 Natural Carbonates of Calcium and Mag- 

 nesium in Relation to the Chemical Com- 

 position, Bacterial Contents, and Crop- 

 Producing Power of Two Very Acid Soils . 119-125 



Oats. Sec Avena saiha. 



Oleander, yellow. See Thevetia nerii folia. 



Opius humilii, parasite of Ceratitis capitata. . 441-446 



Orange, Chinese. See Citrus sp. 



Organic extracts, effect on citrus seedlings in 

 water cultures 267-274 



Page 



Organic matter — 

 effect on solutions toxic to citrus solutions. 270 

 loss in making brown and black alfalfa. . 299-304 

 Oscinis — 



alricilla, pest of oats 466 



carbonaria. Syn. Oscinis frit, 

 frit— 



distribution 4S3-4S4 



food plants 464-465 



instars 454-457 



life history 458-463 



parasites 471-472 



nigra. Syn. Oscinis frit, 

 nilidissima. Syn. Oscinis carbonaria. 

 pusilla. Syn. Oscinis frit. 

 soror. Syn. Oscinis frit. 



umbrosa, found in oats 470 



xariabilis. Syn. Oscinis frit. 

 Oxalic acid. See Acid, oxalic. 

 Oxid— 

 aluminum, effect of sodium-sulphate tol- 

 erance of wheat seedlings 353 



calcium — 

 effect on — 

 sodium-bicarbonate tolerance of wheat 



seedlings 353-354 



sodium-chlorid tolerance of wheat 



seedlings 352-3S3 



sodium-sulphate tolerance of wheat 



seedlings 352-354-356 



ratio to magnesium oxid in acid soils 

 treated with carbonates of calcium and 



magnesium 122-124 



ferric, effect of sodium-sulphate tolerance of 



wheat seedlings 353 



magnesium, ratio to calcium oxid in acid 

 soils treated with carbonates of calcium 



and magnesium 122-124 



Oxidation of sulphur in soils, effect on solu- 

 bility of rock phosphate and on nitrifica- 

 tion 329-345 



Oxygen, effect on apple-scald 212 



Ozone, effect on apple-scald 212-213 



Ozoniumomnivorum, cause of cotton rootrot. 305-310 



Papaipema nitela at light traps 477-481 



Pareuchaeies tenera at light traps 477-481 



Pathology of Dourine with Special Reference 

 to the Microscopic Changes in Nerve Tissues 



and Other Structures (paper) 145-154 



Peach. See Amygdalus persica. 

 Peanut. See Arachis hypogaca. 

 Peat extract, effect on root elongation of citrus 



seedlings 268-269 



Penicillitim expansum, enzymic activity of 



spores 195-209. 538-542 



Penstemon spp., hosts of Sclerotium rolfsii 129 



Pentosans — 

 in cortex and interior tissue of potatoes . . 286-287 



in juice of Sorghum, vulgare 17-22 



in potato tubers attacked by Pythium 



debaryanum 277-278 



in yellow-berry wheat 167 



Pepper. See Capsicuin annum. 

 Perennials, relationship to annuals and bien- 

 nials 579-581 



Peridroma saucia, experimental host of Soro- 

 sporella uvella 432-436 



