Hatching, grasshopper eggs, 36.
Heading of wheat, 265.

Heat and chlorophyl, 38, 75.

fractional parts, 223, 232.
germination, 137.
harvest, 23.

plant development, 221.
respiration, 19, 48.
ripening of grain, 73.

solar, and latitude, 91, 219.
Heer, climatic zones, 221.

Heidelberg, Germany, insolation, 82.
intensity of sunshine, 93.

plant development, 231.

Heiden, germination and light, 44.
Heinrich, crops and water, 119.
Hellriegel, fixation of nitrogen, 136, 151–155.
shade and plant development, 79.
water and crops, 117.
Helmersen, fruit trees, 231.
Henry, phenological observations, 292.
Heraeus, fixation of nitrogen, 139.
Heredity and acclimatization, 295–308.
Herodotus, climate of Assyria, 296.
Himalayas, grasses, 299.

sun temperatures, 238.

Hochgebirge, sun temperatures, 238.

Hoehner, transpiration, 112.

Hoffmann, phenological investigations, 236-243.

phenological notation, 291.

thermal constants, 174.

Holter, grasses, 311.

Hooker, black-bulb temperatures, 238.

Hop vines, pruning, 341.

Horse chestnut, phenology, 280.

Hough, phenology, 5.

Houghton Farm, N. Y., soil temperatures, 53, 66.

Humboldt, germination, 45.

phenology, 72.

sunshine, 169.

Hunt, germination, 307.

maize experiments, 334, 335.

Huron, S. Dak., meteorological data, 320-330.
Hydrocarbons, 17.

Hygrometric data, 273.

Iberis amara, germination, 28-36.

Iceland, acclimatization, 217.

Ihne, phenological notation, 291.

Ilionkoff, crops and water, 116.

Illinois, maize experiments, 334-335.

"Inclosure" of the thermometer, 238.
Indiana, maize experiments, 33.
Ineffective temperatures, 34-36.
Ingenhousz, germination, 42.
Initial date, 238.

point in phenology, 168-189, 213, 214, 218.
temperature, 279–290.

Inoculation of soils, 136-161.

Insolation, measurement, 82, 90, 91.

compensation, theory of, 219.

Instructions, phenological, 291.

International Meteorological Tables, 101.

Irkutsk, Siberia, cereals, 187.

Irrigation, 23, 234.

acclimatization, 362.

crop yield, 116.

Leone, nitrification, 160.

sources of nitrogen, 160.

Lepidium sativum, germination, 28–36.

Leyst, earth temperatures, 65.

Libbey, sunshine tables, 101, 102.

Light, and absorption of oxygen, 47, 48, 50, 51.
germination, 37, 42-52.

Pauchon's experiments, 45.
respiration, 19.

vegetation, 26, 40, 79, 80.

Lightning and fixation of nitrogen, 135.

Lilac, phenology of, 280–290.

Limit of cultivation, 187.
Linden, phenology, 281-290.

Linsser, laws of acclimatization, 7, 215, 242.
phenological studies, 6, 211-234.
sunlight and vegetation, 218, 219.
thermal constants, 173.

zones, 224.

Linum usitatissimum, germination, 28-36.

Lippincott, dates of sowing and harvest, 359–361.

phenology of wheat, 179.

Lisbon, Portugal, intensity of sunshine, 94.

photochemical researches, 94.

Lobositz, Austria, rainfall and harvest, 111
Locality, influence on vegetation, 183.
Lonicera alpigena, phenology, 237.
Lucerne, fixation of nitrogen, 137, 153.

water consumption, 113.

Lucimeter, Bellani, 99, 273.

Lupin, fixation of nitrogen, 153, 160.

Lynden (North Cape) Norway, wheat, 39
gluten in wheat, 41.

McLeod, soil temperatures, 63.

Madeira, seasons, 221–232.

Maize, acclimatization, 220.

albuminoids, 18.

date of ripening, 125.

environment, 314.

experiments with, 321-334.

fertilizers, 162.

thermal constants, 335-337.

Manche, France, climate and crops, 175.
Manchester, England, insolation, 82.

photochemical action of daylight, 93.

Mangon, chlorophyl, 76.

initial temperatures, 279.

thermal constants, 174, 252, 265.

Manitoba, Canada, forest experiments, 128.
Manures, 162-166.

and crops, 121.

soil temperatures, 54.

Maquenne, nitrogen and vegetation, 139.
Marcano, lightning and nitrogen, 135.
Marchand, actinometer, 96, 273.

shade and plant development, 79.
Marié-Davy, acclimatization of plants, 41.
actinometer, 273.

actinometric results, 96.
chlorophyl, 75.

maize, 170.

meteorology and crops, 247-251.
phenological constant, 176, 177.

phenological researches, 243–277.
prediction of harvest, 178.
radiation, measurement, 81.

sunshine and transpiration, 69, 70, 113.

Marié-Davy, water and crops, 246.

Martins, thermal constant, 278.

Martins, von, light and vegetation, 27.
Marvin, sunshine recorder, 99.

Mascagno, light and assimilation, 78.
Matotschkin-Schar, Nova Zembla, acclimatiza-
tion, 216.

thermal constants, 216.

Maurer, soil temperatures, 21.

Maximum temperature of germination, 34.
Mecklenburg, Germany, water and plant develop-

ment, 119.

Meech, sunshine tables, 101.

Meigs, phenology, 292.

Melon (canteloupe), germination, 28-36.
Mendenhall, soil thermometers, 66.

Meteorology and crops, 247-251.
Mexico, origin of maize, 234.
Meyen, germination, 44.

Michael, botanical classification, 68.

Miesse, germination and light, 42.
Mikosh, chlorophyl, 38.

Milk, souring, 341.

Millet, silkworms, 36.

Minimum temperature of germination, 33, 34, 335.
Miquel, collection of germs, 131.
Modification of plants, 233.

Moisson, respiration of plants, 18.
Moisture and germination, 37.

plant development, 222.

records, 273.

soil, 20, 104, 110-111.

Moleschott, light and vegetation, 37, 39.

Montreal, Canada, soil temperatures, 63, 64.

Montrouge, France, flowering of wheat, 178.
Montsouris, France, actinometric percentages, 87.
actinometric degrees, 89, 96.

atmospheric electricity, 131, 132.
bacteriology of air, 130, 131.

Bellani lucimeter, 98.

evaporation data, 105, 106.

insolation and transpiration, 71.

intensity of sunshine, 89.

nitrogen in rain, 133, 134.

researches, 243, 277.

variations in atmospheric air, 133.

Morley, variations in atmospheric air, 133.
Morren, acclimatization, 220.

germination, 43.
phenology, 167.

Mulder, protein, 17.

Munich, phenology, 186.

soil temperatures, 54, 55, 57.

Müntz, fixation of nitrogen by lightning, 135.
nitrifying ferment, 142.
Müttrich, forestry, 7.

Naples, phenology, 184, 185.

Narcissus, phenology, 280, 282.
Nertchinsk, Siberia, cereals, 187.

New York State, maize experiments, 332, 333.
phenological observations, 235, 292.
Nigella sativa, germination, 28-36.
Nitrates in sugar beets, 262.

Nitrogen, artificial fertilizers, 162.

fixation by plants, 136-161.
by soils, 139.

in rain, 133-135.

Nitrogen, loss from soils, 141, 142.
nitrifying bacteria, 148, 149.
plant nutrition, 133, 141, 364.
sugar beets, 262.

Nobbe, germination, 44.

Nordlinger, variations of temperature in forests, 7.

Normandy, thermal constants, 175, 176.
North Cape, Norway, germination, 39.
gluten in wheat, 41.

Norway, acclimatization, 220.

rye, 41.

Notation, phenological, 291, 293.
Nutrition, rôle of water, 114.

of plants, 22, 140.

Oak, phenology, 281–290.

water consumption, 113.

Oats, cellulose, 18.

drought, 337, 338.

environment, 314.
fertilizers, 162.

light, 39.

nitrogen, 136.

phenological constant, 177.

thermal constants, 320.

Turkish, 217.

water consumption, 113, 123.

Observations, phenological, 290–294.

Ohio, oats in, 338.

Optimum temperature, 36.

Orange, France, thermal constant of wheat, 39.

Oregon, soil temperatures, 62.

Orel, Russia, plant development, 231.

Orenburg, Russia, acclimatization, 231.

season of vegetation, 221.

Orkneys, plant development, 39.

Orleansville, Algeria, thermal constants, 176.
Orotava, Teneriffe, acclimatization garden, 221.
Oxygen, absorption by plants, 18, 47–52.
absorption by seeds, 46, 50.

in asparagin, 49.

Ozone and thunderstorms, 341.

Pagnoul, assimilation, 78, 79.

fixation of nitrogen, 150, 161.
sugar beets, 259-263.

Papilionaceæ, fixation of nitrogen, 157.
Para, Brazil, insolation, 82.

photochemical researches, 93, 94.

Paris, France, germination of wheat, 39.
insolation, 82.

See, also, Montsouris.

Parma, Italy, phenology, 185.

plant development, 231.

Pasteur, light and vegetation, 37.

modification of bacteria, 157.

Pauchon, light and germination, 37, 42-52.

northern vegetation, 40.

Peas, albuminoids, 18.

fixation of nitrogen, 136, 153, 155, 160.

thermal constant, 335-337.

time of flowering, 242.

water consumption, 113, 124.

Penhallow, soil temperatures, 53, 63.

Pendleton, Oreg., soil temperatures, 62, 63.

Pennsylvania, maize experiments, 333-334.

Pentads, in phenology, 273-274.

Pepper, acclimatization, 307.

Percolation, 109.

Periodic variation of climate, 297.
Periodical phenomena, 232.

Perret, water and plant nutrition, 114.
Petermann, fixation of nitrogen, 161.
Pfeffer, asparagin, 49.

thermal constants, 241.

Phantupimeter, 96, 273.

Phenological observations, 290–294.

Phenology, 167-294.

climatic tables, 272-277.

epochs of, 167, 181.

Linsser's law, 214, 215.

lists of plants, 172, 191, 226, 242, 243.

temperature, 172, 211.

thermal constants, 336.

summation of temperature, 279–290.

Philadelphia, Pa., bacteriological examination of
air, 130.

Photantupimeter, 96, 273.

Photochemistry of sunshine, 92.

Photographic measurement of sunshine, 95.

Physiological constant, 224-230.

Physiological method, 6.

Piche evaporimeter, 106, 246, 273.

Pieper, germination, 44.

Pine, water consumption, 113.

chlorophyl and light, 38.
Pinus. See Pine.

Plant growth, 15, 244, 245.
respiration, 18.

Plants, acclimatization, 215.

and air, 18.

climate, 22.

fixation of nitrogen, 136-161.

phenological lists, 172, 191, 226, 239, 240.
soil moisture, 114.

sunshine, 168.

temperature, 53, 235, 236.
water drainage, 115.
water supply, 116–127.
Plat experiments, 352-355.
Plumb, maize, 332–333.

plat experiments, 353.

Poa pratensis, 299, 307.

Poggioli, light and vegetation, 26.

Polar region, vegetation, 39.

Pollen, dissemination, 129, 291.

Polperro, England, epoch of awakening, 184, 185.
Postelberg, Austria, rainfall and harvest, 111.

Potato, cellulose, 18.

date of planting, 309, 310.

dryness and sunlight, 80.

harvest and water supply, 127.

water consumption, 113-119.

Potsdam, Germany, atmospheric electricity, 131.

Pouillet, actinometer, 82.

Poulkova, Russia, phenology, 213–215.

Prazmoffski, fixation of nitrogen, 151-155.

Prediction of crop, 247-251, 363.

tables for, 272-277.

time of harvest, 175, 189.

Prillieux, nitrifying bacteria, 152,

Prize crops, 164.

Progress of vegetation, 183, 185.

Protection from frost, 340.

Protein, 17.

Protoplasm, 16.

Pruning and climate, 341, 363, 364.
Pyrus communis, 242.

malus, 242.

Quetelet, phenological constants, 181-189, 212.
soil temperatures, 235.

time of germination, 37.

Quinchuqui, Colombia (?), wheat and tempera-
ture, 180.

Radau, measurement of radiation, 81, 96.
Radiation, conjugate thermometers, 89.

data for phenology, 273.
influence on plants, 16.
measurement of, 81, 89.
plant development, 170.
soil temperatures, 20, 53.
thermometer readings, 235.

wheat harvest, 253, 254, 269–271.
Radiometer, Bellani, 97, 273.
Rain, nitrogen in, 133-135.

soil temperatures, 54, 110.
sugar crop, 344-350.

Rainfall and crop yield, 116–127, 253.

data for phenology, 273.

plant development, 223, 234, 235, 245.
soil moisture, 110-111.

sugar beets, 125, 260.

wheat crop, 341–343.

Rainy days, and plant growth, 117.

soil moisture, 111.

Range of germination temperatures, 35.
Rape, water consumption, 120.

Rawson, rain and sugar in Barbados, 344-350.
Réaumur, thermal constants, 168.
Reforestation, 231.

Respiration, influence of light, 22, 37, 50.
plants and seeds, 18, 47-48, 50.
temperature, 19, 48.

Rhone, cold waves, 129.

Ribes rubrum, phenology, 280.

Richardson, grain and environment, 312-314.
Richmond, Va., wheat and temperature, 180.
Ripening, epoch of, 182, 186.

latitude, 243.

period, 183.

thermal constant, 169, 173, 191, 226, 278-290.
vine, 257.

wheat, 253, 267.

Risler, water consumed by plants, 113, 246.
Robinet, silk worms, 36.

Roscoe, measurement of sunshine, 82.

photochemical researches, 92.

Rotation of crops, 141, 144, 157.

and artificial fertilizers, 162–166.

Rothamsted, England, composition of rain, 135.

evaporation and crops, 245.

fertilizers, 138, 142, 145.

plat experiments, 355.

Royer, available moisture, 111.
Russell, evaporation, 106.

Russia, acclimatization of wheat, 220.
Rye, growing period, 243.
phenology, 280-290.

water consumption, 113, 120, 124.

Sachs, climatic laboratory, 24.
chlorophyl, 38, 39.

light and vegetation, 26, 78.

Sachs, limiting temperatures, 174, 335, 339.
physiological studies, 6.

tuber growth, 79, 80.

ultraviolet light and plant growth, 80.
Sainfoin, fixation of nitrogen, 153.
St. Louis, electricity of air, 131, 182.
St. Petersburg, phenology, 214.
thermal constants, 214, 216.
sunshine, 219.

Salfeld, inoculation of soil, 158.
Salkowsky, nitrifying bacteria, 139.

Sambucus nigra, phenology, 281.

Sanborn, fertilizers, 162.

Saunders, thaws and plant life, 128.

Saussure, de, germination, 43.

Schleiden, potato and light, 39.

Schloesing, ammonia in soils, 136, 142, 143.
atmospheric ammonia, 144.

nitric ferment, 142.

Schloesing, jr., fixation of nitrogen, 150, 151.
Schott, sunshine tables, 101.
Schuebeler, acclimatization, 217, 220.
climate and plants, 40.

culture of grain in Europe, 243–247.
Schweitzer, maize experiments, 333.
Seeds, germination, 28, 41-52.

relations to air and soil, 18.
Seeding. See Sowing.

and harvest, 358-361.

Seignette, available moisture, 111.
Sendtner, phenological list, 189.
Sénébier, light and germination, 42.

light and vegetation, 26.

Serafina, germs and forests, 130.
Serradella, fixation of nitrogen, 160.
Sesamum orientale, germination, 28–36.
Seynes, de, germination, 33.

Shade, and plant development, 79.

temperature, 238.

Sidération, 158.

Silver chloride, measurement of sunshine, 92.
Sinapis alba, germination, 28-36.

Singer, rain and soil temperature, 54.

Six, soil thermometers, 65.

Smithsonian Meteorological Tables, 101.
Smithsonian phenological list, 292–294.
Smut, wheat, prevention, 341.

Soaking, influence on germination, 37.
Soda, nitrate of, fertilizer, 163.
Soil, ammonia, 136, 139.

cereals, 364.

evaporation, 246.
exhaustion, 142.

moisture, 20, 104–127.

temperature, 20, 53-65, 235, 273.
thermometers, 21, 65, 66.

wheat, 314-318.

Solar constant, 91.

Sorauer, water consumption, 123.
Sorghum, 337.

South America, seasons, 221.

South Carolina, prize corn crop, 164.

Sowing, date of, and wheat harvest, 263-272, 358–361.

and crop yield, 337, 339, 355-358.

Spörer, acclimatization of grasses, 299.
Sports, origin of, 303, 362.

Starch and light, 41.

composition, 17.

Statistical method in botany, 7.

Stettin, Germany, phenology, 186.

Stone, sorghum, 337.

Structure of seeds, 35.

Sturtevant, cultivation and evaporation, 108.
pepper, 307.

range of plants, 9.

thermal constants, 335-337.

Stuttgart, Germany, acclimatization, 220, 233.

Sugar beets, and climate, 259–263.

rainfall, 125.

time of harvest, 310.

Sugar crop and rain, Barbados, 344-350.

climate, 363.

Summation of temperature, 279–290.

Sunshine and absorption by seeds, 47, 48.

assimilation, 67–80.

chlorophyl, 75.

diminution, 99.

distribution, 72.

dust and diffused sunshine, 81.

effects, 22.

hour degrees, 74.

latitude, 244.

measurement, 22, 81-103.

Montsouris, 89, 90.

photochemical intensity, 92.
photographic measurement, 95.
plant development, 160, 244, 247.
recorder, 21.
records, 99, 100.

ripening of grain, 73.

soil temperatures, 20.

sugar beets, 259.

total possible, 101-103, 219.

transpiration, 69.

wheat crops, 255.

Sun temperatures, 238.

Surface slope and soil temperature, 57.

Sweden, phenology, 186.

Switzerland, acclimatization of grains, 220.
Symbiotic life, 138.

Tables of possible sunshine, 101-103.

Taimyr, Siberia, grasses, 299.

Temperature, black bulb, 171.

chlorophyl, 38.

effective, 170.

germination, 28-36.

ineffective, 36.

low, and vegetation, 338-340.

phenology, 211, 273.

plant development, 19, 168, 211, 234, 236, 239.

respiration, 19, 48, 50.

soil, 20, 53-66.

sugar beets, 260.

summation, 279–290.

wheat crop, 341-343.

Teneriffe, botanical garden, 221.

Tessier, light and vegetation, 6.

Thaws and plant life, 128, 237.

Theory of compensation, 219.

Theory of errors in agriculture, 353, 354.

Thermal constants, 168, 189-191, 236-243, 278-290,

320-331.

barley, 319.

grape, 256-259.

2667-05 M- -25

Thermal constants, maize, 336.

oats, 320.

peas, 336.

wheat, 251-256, 265, 267, 278, 319.
Thermoelectric actinometer, 99.
Thermoelectric sunshine recorder, 97.
Thermometer, soil, 21, 65, 66.

Thermometric constants and plant growth, 168.
Thermometric measurement of sunshine, 83-92,

96.

Thermophone, 65.

Thorpe, insolation measurements, 82.

photochemical researches, 94.

Thunderstorms, and souring of milk, 341.

and nitrates, 135.

Thuya, chlorophyl and light, 38.

Tilia europeæa, Tilia silvestris, phenology, 281.
Timiriazeff, chlorophyl, 38, 41.

Timothy, cellulose, 18.

time of harvest, 310.

Tisserand, grain culture in Europe, 243–247.
light and vegetation, 41.
sunshine and grain, 73.

vegetation in high latitudes, 40.
Tokyo, Japan, soil temperature, 54.
Tomaschek, thermal constants, 173.
Transmission of solar heat, 92.
Transpiration, 19, 112.

diurnal periodicity, 70.

plant temperature, 53.
and sunshine, 67–80.

Treadwell, souring of milk, 341.

Trees and rapid thaws, 128.

Trifolium repens, germination, 28–36.

Tubercles, on nitrogen-fixing plants, 136, 137.

Tubers, dryness and sunlight, 80.

Ultraviolet light and plant growth, 80.

United States, average wheat crop, 179.
crops and climates, 351-364.
evaporation, 107.

phenology, 186.

Upsala, Sweden, germination of wheat, 39.
phenological observations, 241–242.

Valognes, France, epoch of awakening, 185.
Van Tieghem, phenological constants, 179.
Vegetation, annual progress, 183.

beginning of, 238.
climatic factors, 188.
development of, 232.
high latitudes, 40.
Linsser's law, 214, 215.
thermoscope, 174.

wind, 129.

zones, 224.

Venice, Italy, phenology, 185.

plant development, 31.

sunshine, 219.

Vienna, Austria, phenology, 189, 190.

plant development, 231.

thermal constants, 238.

Ville, atmospheric ammonia, 144.

fertilization by clover, 158.

fixation of nitrogen, 146, 153, 155, 159.
germination, 44.

Vilmorin, thermometer exposure, 176.