1208 
Journal o f Agricultural Research 
Vel XXXI 
Page 
Nevens, W. B., and Gaines, W. L.; Growth- 
equation Constants in Crop Studies... 973-985 
Night and Day. See Day and Night. 
Nitrate and Nitrogen, Influence Upon the 
Protein Content and Yield of Wheat: 
Edmund Burke_1189-1199 
Nitrates, soil, relation to— 
ammonia content of soil_ 549-553 
yields and protein content of wheat_1193-1196 
Nitrogen- 
Constituents of Celery Plants in Health 
and Disease: G. H. Coons and L. J. 
Klotz_ 287-300 
effect of disease of grapes on_ 287 
Metabolism in Etiolated Corn Seedlings: 
S. L. Jodidi_ 1149-1164 
Nitrate, Influence Upon the Protein Con¬ 
tent and Yield of Wheat: Edmund 
Burke- 1189-1199 
percentage in corn_ 184-185 
study in metabolism, experiments_ 1069-1070 
variation in plant substances with disease, 
etc_ 287-288 
water soluble— 
distribution in etiolated corn seed¬ 
lings- 1157-1160 
partition in etiolated corn seedlings. __ 1159 
Noble fir. See Fir; Firs. 
Nodule organisms, study by use of milk, 
litmus, brom-cresol purple, and janus- 
green---:_ 997-1000 
Nordby, J. E., and Snyder, Robert S.: In¬ 
fluence of Field-pea Rations on the 
Quality of Pork_ 1173-1178 
Nursery Practice, Western Yellow Pine, 
Studies: Donald R. Brewster and J. A. 
Larsen_ 1101-1120 
Nutrition, effect of sodium variation in a 
wheat ration_ 365-375 
Nutritive Value of Wheat: I.—Effect of 
Variation of Sodium in a Wheat Ration: 
George A. Olson and J. L. St. John_ 365-375 
O’Donnell, F. G., Marshall, Rush P., and 
Hunt, N. Rex: Steam and Chemical 
Soil Disinfection with Special Reference 
to Potato Wart_ 301-363 
Olson, George A., and St. John, J. L.: The 
Nutritive Value of Wheat: I.—Effect 
of Variation of Sodium in a Wheat 
Ration_ 365-375 
Onion- 
wild, reproduction by bulblet_ 282 
Winterbeck, smut infection, experiments 282-283 
Onions— 
bulblet reproducing, immunity from smut 282 
smut- 
origin- 285 
susceptibility, conclusions_ 285-286 
Susceptibility of Varieties of and of Spe¬ 
cies of Allium to Urocystis cepulae: P. J. 
Anderson_ 275-286 
varieties, experiments for infection with 
Urocystis cepulae _ 276-277 
Ophiobolus graminis Sacc.— 
and the Take-all Disease of Wheat, Stud¬ 
ies: Ray J. Davis_ 801-825 
growth and sporulation, effect of light_812-813 
influence of hydrogen-ion concentration 
on growth- 808-812 
Influence of Soil Temperature and Mois¬ 
ture on Infection of Young Wheat 
Plants: H. H. McKinney and R. J. 
Davis___ 827-840 
morphology_ 803-805 
overwintering_816-818 
pathogenicity_813-816 
Ophiobolus heterostrophus , n. sp.— 
ascigerous stage_ 716-721 
classification__ 721-725 
conidial stage_ 703-705 
in The Ascigerous Stage of a Helmintho- 
sporium Exhibiting Bipolar Germina¬ 
tion, Cause of Leaf Spot of Maize: 
Charles Drechsler_ 701-726 
Ophthalmia, development from rancid lard 1024 
Osmotic concentration in terms of freezing- 
point depression in Egyptian, Sea- 
island, and Upland cotton_ 1027-1033 
Page 
Pacific Coast, comparison of regions in 
study of fruit-bud formation:_ 880 
Palm. See Date palm. 
Paraffin oil, interfacial tension in solution.. 76 
Parasites, wheat, Ophiobolus graminis, 
influence of soil temperature and mois¬ 
ture- 827-840 
Parman, D. C.: Benzene as a Larvicide for 
Screw Worms- 885-899 
Pea and barley ration, hogs, relation to best 
dressing percentage_1173-1178 
Peach, stocks resistant to crown gall_ 960-969 
Pear— 
and Apricot, Fruit-bud Formation Influ¬ 
enced by Certain Environmental and 
Cultural Conditions: C. B. Wiggans... 865-883 
fruit buds, differentiation and develop¬ 
ment_ 869-873,878-879 
Peas, use in combinations for finishing hogs, 
comparison_ 1176 
Pedigrees, Livestock, Approximate Method 
of Calculating Coefficients of Inbreed¬ 
ing and Relationship: Sewall Wright 
and Hugh C. McPhee_ 377-383 
Penetration, soil, by fungicides_ 329-357 
Pepper, inoculation with mosaic, and 
symptoms_ 47-49 
Pest, control by use of vacuum_ 1035-1041 
Phaseolus vulgaris, varietal tests for disease 
resistance_101-154 
Phoenix dactylifera — 
growth temperature minimum, and 
absence of resting period_ 401-414 
importance_ 415 
Phosphate rock, decomposition, effect of 
colloidal silica_ 254-256 
Phosphates— 
Efficiency, Relation to Colloidal Silica: 
P. L. Gile and J..G. Smith_ 247-260 
fertilizing efficiency variation with soils.. 247-249 
Phosphorus— 
pentoxide, corn and sunflower, compari¬ 
son_ 1171 
percentage in corn_ 186-187 
Phytolacca decandra, agency in overwinter¬ 
ing of mosaic disease_ 32-42 
Phytophaga destructor Say, Behavior Under 
Conditions Imposed by Emergence 
Cages: Walter H. Larrimer_ 567-574 
Pieters, A. J.: Difference of Internode 
Lengths between, and Effects of Varia¬ 
tions in Light Duration Upon, Seed¬ 
lings of Annual and Biennial White 
Sweet Clover_ 585-596 
Pigweed, mosaic of, cross inoculation with 
cucumber, and symptoms_ 52-55 
Pine— 
heights, method of obtaining_ 1122 
Pure Yellow Type, Yield Capacities on 
the East Slope of the Sierra Nevada 
Mountains in California: S. B. Show..1121-1135 
rust- 
cell fusions, catenulate spores, and 
intercalary elements_ 643-647 
Gallowaya pinicola Arth., Organization 
of the Telial Sorus: B. O. Dodge_ 641-651 
peri dial buffer tissue_ 643 
seed— 
bed, covering depth_1102-1108 
western white-pine, greenhouse germi¬ 
nation_ 896 
Seed, Western White-pine, Germination, 
Methods of Stimulating: J. A. Larsen. 889-899 
western— 
White and Noble and Silver Fir and 
Douglas Fir, Laboratory Tests: J. V. 
Hofmann_ 197-199 
yellow, method of sowing_ 1109,1110 
Yellow, Studies in Nursery Practice: 
Donald R. Brewster and J. A. Lar¬ 
sen_ 1101-1120 
White. See White pine, 
yellow— 
dominant mature heights in virgin for¬ 
ests as indices of site_ 1124-1126,1135 
increment borer used for age determi¬ 
nation_ 1131-1133,1135 
new standards of utilization_ 1135 
