The forms of P in 24 soils were determined by chemical fractionation. The available P was determined by plant growth experiments. Regression analysis of the P fractions with available P showed that iron P explained most of the variation. Water-soluble P was the only other fraction significantly contributing to the explained variation.

The triglycerides of a Congo palm oil were separated into fractions with 0, 1, 2, 3, and 4 double bonds by thin-layer chromatography using silica gel impregnated with silver nitrate as adsorbent. The amounts and fatty acid compositions of these fractions were determined. In addition, the fatty acid compositions at the 2-positions of the palm oil and of the triglyceride fractions were determined by lipase splitting. The analytical results allow an accurate determination of the triglyceride composition. The results confirm the correctness of Vander Wal's theory on the distribution of fatty acids in triglycerides of natural fats.

Surface area was determined from ethylene glycol (EG) retained by vapor-wetted soils and clays in equilibrium with EG-bentonite or -resin buffers. The method compared favorably with previously proposed equilibrium and nonequilibrium methods. Only small excesses of EG are adsorbed by vapor-wetted samples. This reduces equilibration time, extends buffer life, and eliminates hysteresis on the drying curve at the monolayer point. The determination is independent of sample size; moderate temperature fluctuations; or moisture present in EG, buffer, or sample. Use of redistilled EG is not necessary. The monolayer end point can be determined using a series of EG-bentonite buffers independently of other methods. Buffers containing more than a monolayer of EG can be used if suitable corrections are made.

Thermal conductivity and volumetric heat capacity of a soil near its surface are in situ simultaneously determined using a heat flux plate on the soil surface and thermocouples in the soil. The rise of the temperature caused by a heat pulse of short duration is recorded. The time involved in numerical calculations is greatly reduced by the use of Laplace transforms of heat flux density and rise of temperature. The heat flux into the soil under natural conditions can be calculated from the temperature recorded in the absence of the heat flux plate using the thermal conductivity as it has been determined. The method is applied to a sand soil and to a peat mulch on sand, which were at uniform initial temperature. Theory is emphasized. A discussion of some experimental problems, met in in situ determinations, will be given in a subsequent paper.

In this paper the authors describe the results obtained from the determination of molybdenum in sugar cane plant, grown in soils and climate prevailing in Piracicaba, State of São Paulo, Brazil. The molybdenum was determined in samples cut monthly from the 8th to 14th month, from an experiment consisting of 6 plots, 3 fertilized and 3 unfertilized. The fertilized treatment received 40 kg N (ammonium sulfate) 100 kg P2O3, (superphosphate) and 40 kg K2O (potassium chloride) per hectare, just before planting. Molybdenum was determined by thiocyanate-stannous chloride method, using carbon tetrachloride-butyl alcohol misture, for extrating the colored complex. The results obtained show a parallelism in the absorption of molybdenum by the plants of both treatments. The concentration of molybdenum in the stalks have a tendency to decrease, where as it kept more or less constant in leaves, with a exception in the 14° month when it rised probable because of a migration of molybdenum of the stalks to the leaves. The total amount molybdenum taken up was higher with the fertilized plot due its greater mass prodution.

The quantities of ethanolamine glycerophosphatides (EGP), choline glycerophosphatides (CGP), and serine glycerophosphatides (SGP) were determined in the grey and white matter from three apparently normal adult human brains. In each locale the quantities decreased from EGP through CGP to SGP.The quantities of aldehydes in these lipids were also determined. In grey matter the aldehyde content (expressed as per cent of fatty acids plus aldehydes) of EGP, CGP, and SGP was 22, 0.3, and 0.2% respectively; while in white matter the proportions were 49, 0.8, and 13%, respectively. Palmitaldehyde, stearaldehyde, and olealdehyde made up 90% of the aldehydes found. White matter glycerophosphatides contained much more olealdehyde than those from grey matter.EGP and SGP contained much larger proportions of C20 and C22 polyenoic acids from grey matter than from white matter. CGP, on the other hand, had a similar fatty acid composition, comprised mainly of 16:0, 18:0, and 18:1 acids, in each locale. The differences in fatty acid composition of these three glycerophosphatides may be related to the higher myelin content of white matter.

The ratio of lipid C14 in plasma of portal vein blood to that in plasma of systemic blood was determined in chickens killed 30, 60, 90, and 150 min after injection of palmitic acid-1-C14 into their gizzards. In other experiments other ratios were determined: (a) lipid C14 in plasma of pancreaticoduodenal blood to that in portal vein blood in chickens killed 30 min after fatty acid administration; and (b) lipid C14 in jejunal vein to that in portal vein plasma in birds killed 90 and 150 min after the injection. The results demonstrated that the portal system is a significant pathway for the absorption of fatty acid from the intestines of the bird, and that during the early period absorption from the duodenum takes place.Measurement of the C14 remaining in the digestive tract contents indicated that up to 96% of the injected labeled palmitic acid was absorbed in 90 min. Analysis of ultracentrifugally-separated plasma lipoproteins in blood drawn from the pancreaticoduodenal vein half an hour after introduction of the labeled palmitic acid into the gizzard revealed that the palmitic acid was absorbed from the intestines into the bloodstream principally as triglycerides in the very low density (Sf > 20) lipoproteins.

The bioenergetics of the southern harvester ant were studied on the Savannah River Project, Aiken, South Carolina. Excavation of hills revealed that density of ants ranged from 4,000 to 6,000 per hill. Labeling ants with P32 indicated that only 10% of the ants in a colony were active above ground during any 2—week period (the limit of recognition of the label); thus, short—term marking recapture estimates based on above—ground individuals greatly underestimate the size of the colony. There were 27 hills per hectare on the study area. The consumption of oxygen of workers at various temperatures was determined in a simple respirometer, and the temperature at which the ants were living in the field was determined during a year's observation at mounds. The energy expense of heat production was calculated from the oxygen consumption and activity temperature records. Total energy flow (heat production plus tissue growth) was highest in summer and lowest in winter. The annual range was from 14 to 48 kgcal/m2/yr. Tissue growth was estimated to amount to only 0.09 kgcal/m2/yr. Energy flow in this species was higher than that of 2 vertebrate granivores studies in the same field, the old—field mouse and the savannah sparrow.

Field observations are correlated with laboratory experiments (Part I). Instar I larvae are diurnal, instars III to VII larvae nocturnal and instar II larvae intermediate. The entry of instar I larvae into the soil is determined by decrease in light and fall in temperature. The activity of instars III to VII larvae is generally unaffected by temperature but is mainly related to absence of light. Instar I larvae are indifferent to moonlight; instar VII larvae are repelled by it.

A cattle feeding experiment required that nitrate be determined in bovine milk, blood, urine, and rumen liquor. Attempts to apply the phenoldisulfonic acid or brucine procedures to these fluids gave erratic results, despite protein precipitation, chloride removal, and heavy metal precipitation. Application of a xylenol extraction procedure to the clarified solutions gave reproducible results and satisfactory recoveries of added nitrates.