bluuebunny/crossref_metadata_2025 huggingface dataset:
RECENT INVESTIGATIONS ON TOBACCO ROOT ROT IN CANADA
Authors: Koch L. W.
Published: April 2011

These investigations involved the direct microscopic examination of root systems of tobacco plants showing typical macroscopic evidence of infection by Thielaviopsis basicola (Berk.) Ferraris, supplemented by isolations from both diseased and healthy roots and infection experiments with the isolates obtained. Intensive microscopic examination of lesions on approximately 1600 roots affected with typical black root revealed the presence of many different organisms which were found to occur singly, in various combinations with one another and more especially in frequent association with T. basicola. In addition to T. basicola the organisms observed included the following: the so-called phycomycetous type of "mycorrhizal" fungus, representatives of the genus Rhizoctonia, including R. Solani as well as several endophytic forms of the type familiar in orchids, different members of the genus Pythium, and nematodes. In general, members of the Fungi Imperfecti appeared to be conspicuously absent. Microscopic evidence of parasitism on the part of each of the above-mentioned organisms was revealed by necrosis involving single cells, groups of cells or entire rootlets. The phycomycetous "mycorrhizal" fungus resembling in many respects the fungus reported as being almost universally present in the roots of strawberry, immediately upon penetration produces characteristic coils of mycelium in the outer cortical cells, ramifies deeper, and spreads producing first arbuscules and then vesicles in the deeper cortical tissues. Previous investigators (11, 15, 20, 24) have reported this or a closely related form of the fungus only in the roots of host plants. In the present paper it is reported for the first time completely invading the stems and leaves of moss plants, also the thallus of liverworts found growing in muck soil obtained from tobacco seedbeds. Daily microscopic examination of tobacco seedlings developing in muck known to contain the phycomycetous "mycorrhizal" fungus revealed the presence of the latter organism in 30% of the roots as early as five days after germination and in all of them 10 days after germination.Isolation from 206 typically diseased roots has consistently yielded T. basicola as well as representatives of 21 genera of fungi, also bacteria and nematodes. The fungi isolated most frequently in association with T. basicola included representatives of the genera Pythium, Rhizoctonia and Fusarium. Preliminary infection experiments have demonstrated that one Rhizoctonia of the "Solani" type and three endophytes from the same genus, four forms of Pythium as well as T. basicola possess parasitic capability in the roots of tobacco, whereas two other forms of Pythium, three of Rhizoctonia and seven distinct members of the Fungi Imperfecti showed no capability of parasitism of the same host under identical conditions.
TEMPERATURE, WIND, HUMIDITY AND EVAPORATION IN AGRICULTURAL METEOROLOGY
Authors: Hopkins J. W. , James Mabel F.
Published: April 2011

A statistical study has been made of evaporation and allied meteorological observations for a period of approximately 20 years at each of two stations, situated in Montana and New Mexico respectively.The average values, over this period, for May, June, July and August of all four meteorological quantities showed a seasonal trend. At both stations July was the month of maximum average temperature, evaporation and vapor pressure. Average wind velocity was greatest at both stations in May, decreasing progressively throughout the summer.In general the extent of evaporation was markedly influenced by wind and vapor pressure as well as by temperature. Annual variations in evaporation during a specified calendar month were found to be correlated with temperature differences, but here also there was a significant additional effect of wind and vapor pressure. Evaporation measurements should therefore supplement temperature records in agricultural meteorological studies.
STUDIES ON THE INHERITANCE OF AND THE RELATION BETWEEN KERNEL TEXTURE AND PROTEIN CONTENT IN SEVERAL SPRING WHEAT CROSSES
Authors: Aamodt O. S. , Torrie J. H.
Published: April 2011

In crosses of Milturum × Selection I-28-60, F2 populations grown from different F1 plants were found to behave in three different ways in regard to the mode of inheritance of kernel texture. In two of these groups vitreous texture was partially dominant and governed by either one or two main factors, while in the third group starchy texture was partially dominant and governed by one main factor pair. Minor modifying factors also influence the mode of inheritance of this character in the above crosses. The heritable nature of kernel texture was also demonstrated, by correlation studies, in the crosses of Reward with Selections I-28-46, I-28-60 and I-28-62.The inheritance of protein content in Milturum × Selection I-28-60 appeared to be controlled by polymeric factors, the exact nature of which was not determined. The lack of correlation for crude protein content between the material grown at Brooks and that grown at Fallis indicates that the expression of the mode of inheritance of protein content is readily influenced by the environment. In the other crosses studied, protein content was also shown to be inherited.A strong positive relation was found to exist between vitreous kernel texture and high protein content for the several series of crosses studied.
MICROBIOLOGICAL STUDIES OF APPALACHIAN PODSOL SOILS: II. SEASONAL CHANGES IN MICROBIAL ACTIVITY
Authors: Gray P. H. H. , Atkinson H. J.
Published: April 2011

Seasonal fluctuations in numbers of micro-organisms in soil, estimated by the plate method for bacteria and actinomyces and by the evolution of carbon dioxide, have been studied with samples of cultivated podsol soils, drawn from experimental fields under various treatments at three farms in the Eastern Townships region of Quebec, at intervals of six weeks during the cropping season in two years. The nature of the fluctuations in numbers of micro-organisms was similar in the three soils, which were situated many miles apart. In 1931 numbers were lower in summer than in spring and autumn; in 1932 numbers fell towards the end of the season. The evolution of carbon dioxide fluctuated to a comparatively less extent than the bacterial numbers, but there was general agreement in the direction of the changes in the two years. Biological activities in any one soil were at significantly different levels in the two years. There was an agreement between numbers of micro-organisms and the amount of carbon dioxide, in that changes in both of these factors were in the same direction in the second year of sampling; there was also evidence of agreement between intra-annual changes in numbers and carbon dioxide, especially in the alkali-treated plots. Fluctuations in numbers and carbon dioxide in samples from plots in different parts of the same field or farm were in conformity, and were superimposed on the effects of chemical treatments that caused significant increases in microbial activity.
THE INHERITANCE OF DELAYED GERMINATION IN HYBRIDS OF AVENA FATUA AND A. SATIVA
Authors: Johnson L. P. V.
Published: April 2011

The inheritance of germinability was studied in reciprocal crosses between Avena fatua, the seeds of which are non-germinable for several months after harvesting, and A. sativa, the seeds of which are fully germinable shortly after harvesting. The following conclusions were drawn from studies of the first three hybrid generations: (1) Germinability is genetically dominant over non-germinability (delayed germination). (2) There is strong evidence that germinability is inherited on the basis of three factors of more or less equal potency, one of which is linked with the factor for grain type. (3) At the time of testing, embryos having completely recessive genotypes were non-germinable; embryos having genotypes with one dominant allelomorph were non-germinable, except in rare instances; embryos having genotypes with two dominant allelomorphs (of the same or different factors) were to a very great extent germinable; embryos having genotypes with three or more dominant allelomorphs were germinable. (4) The germinative potentialities of genotypes vary with the time elapsing between harvesting and testing. (5) There is some evidence that the linked factor has a greater germinative potency than either of the non-linked factors.
CHARACTER COMBINATIONS IN RELATION TO ENDOSPERM DEVELOPMENT IN INTER-SPECIFIC TRITICUM CROSSES
Authors: Harrington J. B.
Published: April 2011

A study was made of the frequency of different character combinations in relation to seed plumpness in the F2 generation of crosses of T. durum, T. dicoccum and T. persicum with T. vulgare. Some inter-specific character combinations occurred frequently and others were rare, which was expected since the characters varied markedly in their frequency of inter-specific combinations with other characters. The data did not support the popular assumption that inter-specific character combinations of value were to be found largely in plants from shrunken seeds rather than in those from plump seeds. Plants from plump seeds possessed nearly as large a proportion of the combinations which were missing in the plants from shrunken seeds as did the latter plants with respect to the former. The difference could not be considered significant and none of the missing combinations appeared to be important as far as practical breeding is concerned.
A PHOTOELECTRIC PHOTOMETER
Authors: Howlett L. E.
Published: April 2011

A description is given of a photoelectric photometer for measuring general light transmission through glasses, solutions, etc. It is suitable for grading where light transmission is the control. It has been successfully used to measure precisely, quickly and conveniently such quantities as the amounts of dyes removed from solutions by porous bodies, and the concentrations and purities of substances in solution.
PROPAGATION AND RESONANCE OF LONGITUDINAL WAVES IN PRISMATIC RODS
Authors: Ruedy R.
Published: April 2011

For vibrations involving shearing and rotation, and for those involving both distortion and dilatation, the equations of motion combined with the boundary conditions yield in the simplest case a cubic equation for the resonance frequencies; its solution depends on Poisson's ratio and on the resonance frequencies fx, fy, fz, which the rod possesses when in pure shearing motion in the direction of its three axes. Three series of resonance frequencies are obtained when fy and fz are constant and the frequencies of the overtones are inserted for fx. A fourth series of resonance frequencies begins above the highest of the fundamental frequencies fx, fy, fz.
VARIATION WITH TEMPERATURE OF THE PIEZOELECTRIC EFFECT IN QUARTZ
Authors: Pitt Arnold , McKinley D. W. R.
Published: April 2011

As a result of some previous experiments there were indications that the elastic vibrations set up in quartz showed an anomalous property at the temperature of liquid helium. In order to decide this point, experiments were carried out on the piezoelectric activity of quartz at progressively lower temperatures until that of liquid helium was reached. Although a decrease in this activity of only 1% had been observed by others working over the range from room temperature to liquid hydrogen temperatures, the present experiments show a total decrease of 12% at the temperature of liquid helium. Two methods were used, a statical method employed where the temperature could be held constant, and a dynamical method to ascertain the temperature at which any marked change in activity would just become evident. Results by the dynamical method indicate that a sudden decrease in activity occurs at about 5° K. In addition, the dynamical method was extended to higher temperatures, so as to include in this paper values of the piezoelectric activity of quartz from 4° K. to 813° K.
AXIS STRAIN IN THEODOLITES, ITS EFFECTS, AND ONE METHOD OF REMOVAL
Authors: Rannie J. L. , Dennis W. M.
Published: April 2011

Any deviation from geometrical form in close fitting theodolite axes, due to either manufacturing inaccuracies or subsequent dimensional changes in the metals composing them, produces strain in the axes which is transferred through the instrument, and, as the telescope is swung in azimuth, produces deflections of varying amount of the line of collimation. Permanent and variable changes may be produced, also, in the horizontal circle. A method of testing theodolites in the laboratory for the effect of axis strain is described in this paper, together with a method of removing its effect from the alidade and telescope axes of one make of theodolite.
THE HYPERFINE STRUCTURE OF LEAD III
Authors: Crooker A. M.
Published: April 2011

The hyperfine structures in the spectrum of Pb III, excited by an electrodeless discharge, have been studied by means of a 21 ft. concave grating. The hyperfine structure patterns lead to an I-value of [Formula: see text] and a g(I) factor of 1.2 for the odd isotope [Formula: see text], in agreement with the results of previous workers. The isotope shifts between the even isotopes [Formula: see text] and [Formula: see text] are in agreement with Breit's theoretical interpretation, and amount to 0.5 cm.−1 for each 6s electron. The fact that the deep terms in the spectrum of Pb III are rather completely known permits an attempt to be made at a careful comparison between experiment and theory.
AN ELECTRONIC SPEED GOVERNOR
Authors: Ballard B. G.
Published: April 2011

Erratic performance of certain centrifugally governed electric motors prompted a search for a speed control that would be free from the effects of poor contacts, spring creepage, and friction in moving parts. These troubles were overcome by impressing a suitable alternating potential on the motor armature windings so that the rotor turned in synchronism with the alternating current system. The frequency of the latter was determined by a vacuum tube oscillator, and sufficient power obtained by amplifying the oscillator output with an inverter. Subsequent performance has proved very satisfactory.
ALKALI METAL FILMS TRANSPARENT IN THE SCHUMANN REGION
Authors: Watson W. H. , Hurst D. G.
Published: April 2011

Sodium and potassium films deposited from a molecular beam on fluorite at liquid air temperature have been found to be transparent in the Schumann region. For λ > 1400 Å no transparency has been found in the case of lithium. A technique for producing these films is described. The theoretical bearing of these results is discussed.
STUDIES IN THE SPECTRA OF HIGH-FREQUENCY DISCHARGES IN MERCURY VAPOR: II. COMPARISON OF ELECTRODELESS WITH EXTERNAL ELECTRODE EXCITATION: III. MODIFICATION DUE TO WAVE-LENGTH
Authors: Robertson J. K. , Hay R. H.
Published: April 2011

High-frequency discharges in mercury vapor have been excited by valve oscillators, and a comparison made of spectra obtained by the use of a purely electrodeless method with those excited by external electrodes. Temperatures ranged from 100° to over 250 °C., and the use of four wave-lengths of approximate values 5, 35, 75, and 200 m. made it possible at the same time to examine possible changes in the spectrum arising from changing frequencies. It was found that, with the exception of the highest frequency, external electrodes excitation was more effective for the emission of arc and of spark lines, whereas diffuse bands and regions of continuous spectra could be separated from lines at higher pressures somewhat better by electrodeless excitation.Evidence is given that the discharge obtained at a frequency of 60 megacycles differs from that obtained at the lower frequencies. At a low vapor pressure a discharge, which is characterized by great brilliance and the absence of spark lines, is obtained with the highest frequency. There is little to choose between the two types of excitation. An explanation is suggested for the difference due to frequency.
THE SYNTHESIS OF δ-(3-INDOLYL)-VALERIC ACID AND THE EFFECTS OF SOME INDOL ACIDS ON PLANTS
Authors: Manske Richard H. F. , Leitch Leonard Christie
Published: April 2011

The synthesis of δ-3 (indolyl) -valeric acid, by a procedure analogous to that employed in the synthesis of its lower homologues, is described. It, as well as a bz-methyl derivative of β-3(indolyl)-propionic acid, which has also been synthesized, was found to possess the plant physiological properties of a phytohormone.
THE HYDRATION OF DICALCIUM SILICATE AND TRICALCIUM SILICATE
Authors: Keevil N. B. , Thorvaldson T.
Published: April 2011

Samples of β-dicalcium silicate, γ-dicalcium silicate, tricalcium silicate, hillebrandite and dehydrated hillebrandite were exposed to saturated steam at temperatures between 50° and 375 °C. After drying to constant weight (usually over calcium oxide) the increase in weight and the amount of free calcium hydroxide were determined. Microscopic examinations and X-ray diffraction patterns of the products were made. The hydration products were then dehydrated and similar studies of the products made. The hydrolysis of the hydration products also was studied.It was found that between 110° and 350 °C. β- and γ-dicalcium silicates may absorb water without hydrolysis to form three crystalline products. Two of these are identical with products already described (20); the third product appears to possess another characteristic crystalline structure as shown by the X-ray pattern, but to have a variable water content with a limiting composition of 2CaO∙SiO2∙H2O. The hydration product may be dehydrated without the liberation of lime.When conditions favoring hydrolyses are avoided, tricalcium silicate hydrates directly to a crystalline hydrate which probably has the limiting composition, 3CaO∙SiO2∙2H2O, although products holding from 1.3 to 2 moles of water give the same X-ray diffraction pattern. When the conditions favor partial hydrolysis, tricalcium silicate decomposes into calcium hydroxide and crystalline hydrated dicalcium silicate. Dehydration of hydrated tricalcium silicate gives one mole of lime along with dicalcium silicate.Hillebrandite exposed to saturated steam at 160 °C. remained unchanged while a sample of dehydrated hillebrandite on hydration gave a product similar to that obtained from β-dicalcium silicate.When treated with a large excess of water, the hydrated silicates hydrolyze to the same extent as the anhydrous silicates, but the final equilibrium is attained more rapidly, especially in the case of hydrated dicalcium silicate.
THE ELECTRODE POTENTIAL OF IRON IN RELATION TO HYDROGEN ION CONCENTRATION
Authors: Shipley J. W. , Shipley J. H.
Published: April 2011

The electrode potential of iron immersed in phosphate, borate and citrate buffers of varying hydrogen ion concentration was measured, using a normal calomel electrode as the second half of the cell. Breaks in the potential of the iron electrode amounting to as much as 0.7 volts were found to occur at definite pH values for each series of buffers. The electrode exhibited an "initial" and "final" potential depending on the pH of the electrolyte and the time of immersion, the "final" value requiring several days to become established. The "final" break in the electrode potential of 0.74 volts in the pure phosphate buffer occurred between a pH of 3.1 and 4.0, that in the pure borate buffer, of 0.75 volts, occurred between a pH of 4.3 and 4.6, and in the pure citrate buffer, of 0.77 volts, between a pH of 10.1 and 10.9. The effect of chloride ion and de-aeration on the electrode potential was observed. It is suggested that the potential of the iron electrode is determined by the presence or absence of a non electrically conducting film or deposit on the iron, the formation of which is a function of the nature of the electrolyte and its hydrogen ion concentration. De-aeration apparently had no effect on the electrode potential, but the presence of chloride ion affected the establishing of the "final" potential and caused the break in voltage to appear irregularly at a much lower hydrogen ion concentration.At pH values below that at which the break in potential occurred, corrosion of the iron electrode was marked, and the electrode potential remained high, while, at pH values above the break, corrosion was virtually inhibited or confined to local spots on the electrode, and the electrode potential remained low. The presence of the chloride ion stimulated local corrosion and permitted general corrosion to proceed at a lower hydrogen ion concentration.
STUDIES ON LIGNIN AND RELATED COMPOUNDS: XXI. INSOLUBLE METHANOL LIGNIN
Authors: Mackinney Herbert W. , Hibbert Harold
Published: April 2011

When spruce wood meal is extracted with anhydrous methyl alcoholic hydrogen chloride, about 30% of the lignin can be removed in soluble form. The insoluble lignin in the residual wood can be isolated as a fully methylated derivative by a prior complete methylation with dimethyl sulphate followed by hydrolysis with methyl alcoholic hydrogen chloride. The fully methylated insoluble methanol lignin is insoluble in organic solvents.Demethylation experiments followed by subsequent treatment with methylating and acetylating agents, alone or combined, have established a very close relation between the insoluble and the soluble form. The formation of the insoluble form from the native lignin is accompanied by loss of one hydroxyl group as indicated in the two formulas: soluble methanol lignin, C42H32O6(OCH3)6(OH)4, and insoluble methanol lignin (fully methylated), C42H32O6OCH3)9. The new evidence obtained indicates that of the five methoxyl groups present in the original native lignin, at least three are phenolic or enolic in character.
THE POLARIZATION OF LIQUIDS AND THEIR SATURATED VAPORS IN THE CRITICAL TEMPERATURE REGION
Authors: Marsden J. , Maass O.
Published: April 2011

The values of the so-called polarization of methyl ether (liquid and saturated vapor) and propylene (liquid and saturated vapor), from room temperature to the critical temperature, are given. In both liquids this polarization is independent of the temperature to within a few degrees of the critical temperature. Calculations show that the polarizations of a liquid and its saturated vapor may be equal above the critical temperature, even though the dielectric constants of the liquid and its saturated vapor, as well as their densities, are different.
THE SOLUBILITY OF CARBON DIOXIDE IN AQUEOUS SOLUTIONS CONTAINING ALCOHOLS AND SUGARS
Authors: Showalter H. A. , Ferguson J. B.
Published: April 2011

A new type of solubility apparatus is described. The results of the solubility determinations of carbon dioxide at 15 °C. are given for the following systems: alcohol-water, dextrose-water, levulose-water, sucrose-water, dextrose-alcohol-water and sucrose-alcohol-water. Certain incidental measurements of specific gravity and of vapor tension are also given.
CHEESE-RIPENING STUDIES: THE INFLUENCE OF DIFFERENT EXTRACTS ON THE ACID PRODUCTION OF LACTIC ACID BACTERIA
Authors: Sadler Wilfrid , Eagles Blythe Alfred , Bowen John Francis , Wood Alexander James
Published: April 2011

The influence of different extracts on the acid production of two strains of Streptococcus cremoris and two of Betacoccus cremoris isolated from Kingston cheese has been studied.The enriching entity has no effect on acid production by Streptococci in sugar broth. Enrichment with yeast or alfalfa extract causes not only a marked increase in the acid production by Betacocci, but also a definite stimulating effect on the rate of acid production.Enriching milk with yeast or alfalfa extract has a marked stimulating effect on the vital activity of the Betacocci and of Streptococcus EMB1173, but is without influence on Streptococcus EMB1195. The response of culture EMB1173 is immediate and direct, but in the case of cultures EMB2168 and EMB2173 the action of the enriching entity is cumulative in its effect. Alfalfa extract would appear to provide, in the case of Betacoccus EMB2173, a stimulating influence not to be found in yeast extract.The influence of other forage crop enrichments on rate of acid production has also been studied. The factor or factors present in alfalfa and shown to exert a stimulating influence on the vital activity of the organisms are to be found to some extent in all forage crops investigated.
THE CONDUCTIVITY OF ALKALI-WATER-ACETONE SOLUTIONS
Authors: Hatcher W. H. , Mason C. T.
Published: April 2011

Increased acetone concentration in aqueous solutions of sodium hydroxide lowers the specific conductivity to a marked degree. This cannot be satisfactorily explained by viscosity change only, but is probably accounted for by a combination of changes in both viscosity and dielectric properties of the solutions. An empirical equation is suggested.
FATTY ACIDS AND THEIR ESTERS: I. SOME OBSERVATIONS ON THE CRYOSCOPY AND EBULLIOSCOPY OF FATTY ACIDS
Authors: Brocklesby H. N.
Published: April 2011

By the ebullioscopic method and in benzene solution, saturated fatty acids show, with increasing carbon content, a decreasing degree of association up to lauric acid, after which it remains more or less constant. Unsaturation is shown to decrease the extent to which the molecules of fatty acids of the same carbon content associate. The degree of association of oleic acid in several solvents has also been determined.
CHEESE-RIPENING STUDIES: THE INFLUENCE OF THE CONFIGURATIONAL RELATIONS OF THE HEXOSES ON THE SUGAR-FERMENTING ABILITIES OF LACTIC ACID STREPTOCOCCI: A Preliminary Note
Authors: Okulitch Olga , Eagles Blythe Alfred
Published: April 2011

The influence of the configurational relations of the hexoses on the ability of a Streptococcus cremoris strain to produce acid from lactose in milk and in broth has been studied.With casein digest broth as the nitrogen source, the organism was carried by serial transfers in 10 different carbon sources; at every transfer the cultures were inoculated from the sugar broths into milk, and the clotting times of the respective milk tubes determined.The carrying of the culture in sucrose, maltose, dextrin or starch has no influence on the acid-producing ability of the organism.Glucose, mannose, fructose, and salicin exhibit a marked inhibiting effect on the rate and amount of acid production in milk and in lactose broth.Although galactose and lactose fail to inhibit completely the activity of the organism, a restraining influence on acid production is to be observed. It is suggested that the inhibitory activity of glucose or one of its metabolic products may be a cause of the sudden or gradual loss of vitality in starters.
THE ALTERATION OF THE FLOW CHARACTERISTICS AND TEXTURE OF STARCH PASTES
Authors: Gallay Wilfred
Published: April 2011

Starch pastes are classified according to the "length" of the flow or texture, and the practical importance of this characteristic in commercial applications for starch pastes is noted, e.g. for culinary uses. The differences in flow and texture may be attributed to the differences in phase-volume relations and the deformability of the swollen granules in the paste. It is shown that heating in water below the gelatinization point reduces both the volume occupied per unit concentration by the dispersed phase, and also increases the rigidity of the swollen granules. The viscosity of the paste is greatly reduced and the critical concentration of the starches is correspondingly increased by this treatment. The effect is particularly large in the case of potato starch, but is appreciable also with corn and wheat starches. Suspension of starches in dilute sulphurous acid (0.25% SO2) effects a similar change in somewhat greater degree, hence it is probable that the flow characteristics of corn starch are altered during the process of extraction. The practical application of these modifications is briefly discussed.
THE KINETICS OF COUNTERCURRENT ABSORPTION TOWERS
Authors: Littler H. G.
Published: April 2011

The kinetics of countercurrent towers absorbing a gas which obeys Henry's law have been worked out by a more rigid method than that used by Donnan and Masson (2). An equation is obtained which, unlike the Donnan and Masson formula, is the expression of a process which is thermodynamically irreversible. This is in accordance with the requirements of thermodynamics. The theoretical variation of the concentration of the soluble gas in the two phases throughout the tower is examined by means of the new equation.
PEACH CANKER INVESTIGATIONS: II. INFECTION STUDIES
Authors: Willison R. S.
Published: April 2011

Two species of Valsa have been isolated more or less consistently from cankers of various ages, and from "die-back" twigs on the peach. In culture, one species, identified as Valsa leucostoma (Pers.) Fr., is hair-brown and has small dark pycnidia exuding cirri when mature. On the host, its stroma is compact in texture, contains no host cells and is delimited beneath by a black zone of carbonized fungal and host cells. Ascospores of V. leucostoma measure 10–17 by 2–4.5 μ. The other species, which has been assigned to V. cincta Fr., is whitish to olive buff in culture and has large light-colored pycnidia containing, though rarely exuding, spores. On the host, the stroma of V. cincta is comparatively loose in texture, contains host cells and is delimited from the cortex of the host by a thin, black zone, sometimes only marginal. Ascospores of V. cincta measure 14–28 by 4–7 μ. In both species, the pycnospores range from 5 to 10 μ in length and 1 to 2 μ in width. These organisms, along with Sclerotinia fructicola (Wint.) Rehm., were used in series of infection experiments at frequent intervals over a period of two years. Similar series of checks were also provided. Periodical observations and measurements furnished detailed case histories of all wounds concerned. V. cincta was found to be a virulent wound-parasite, able not only to infect freshly made wounds during the late autumn, winter and spring, but also to give rise to perennial cankers. Infection with this organism rarely occurred during June, July and August. V. leucostoma proved in these experiments to be almost, if not quite, incapable of initiating cankers on the peach. S. fructicola parasitized the tissues of branches and produced considerable necrosis during the first three weeks after inoculation during the growing season. Subsequently the lesions proceeded to heal. The degree of infection and the amount of resultant necrosis in wounds inoculated with S. fructicola during the dormant season were dependent upon the conditions of temperature and humidity then prevailing. S. fructicola, while capable of inducing lesions on the stem, cannot be regarded as the cause of typical peach canker. Some of the factors influencing infection by the three organisms mentioned above are briefly discussed.
FLAX STUDIES: I. THE RELATION BETWEEN WEIGHT PER MEASURED BUSHEL, WEIGHT PER THOUSAND KERNELS AND OIL CONTENT OF FLAXSEED
Authors: Geddes W. F. , Lehberg F. H.
Published: April 2011

Determinations of test weight per bushel, weight per 1000 kernels and oil content made on 146 samples of Western Canadian flaxseed, 119 of which graded No. 1 C.W., 16 No. 2 C.W. and 11 No. 3 C.W., revealed that while the grades were differentiated in regard to test weight per bushel and weight per 1000 kernels, the mean oil contents for the three grades were not significantly different. Test weight per bushel is of little significance as an index of oil content. While the degree of association of weight per thousand kernels with oil content is somewhat closer, it is not sufficiently high to permit satisfactory prediction of this variable.
STRIPE RUST, PUCCINIA GLUMARUM, IN CANADA
Authors: Newton Margaret , Johnson T.
Published: April 2011

A study was made of the distribution of Puccinia glumarum (Schm.) Erikss. and Henn. in Canada, its specialization, host range, and reaction to environmental conditions. Unlike Puccinia graminis Pers., this rust has a limited distribution, being confined to British Columbia, Alberta, and the western half of Saskatchewan. The natural hosts include a number of native grasses, particularly Hordeum jubatum L. and certain species of Agropyron, Elymus, and Bromus. Wheat and barley also become infected although to a rather limited extent: Stripe rust collected on the above-mentioned hosts has been studied in the greenhouse and has in all cases shown ability to attack wheat varieties. In all instances where identification of physiologic forms was carried out the rust strains were classified as either form 8 or form 13 of wheat stripe rust, the latter form being the more common. The fact that the present authors have collected known physiologic forms of wheat stripe rust on species of Hordeum, Elymus and Agropyron, and have shown that forms 4, 6, 8 and 13 can attack seedling plants of Hordeum, Agropyron, and Elymus species throw a doubt on the existence of the Hordei, Elymi, and Agropyri varieties created by Eriksson.Greenhouse studies showed that P glumarum is extremely sensitive to environmental conditions, particularly temperature. The optimum for uredospore germination is 10° to 12 °C., and for rust development 13° to 16 °C. Varieties susceptible at from 10° to 16 °C. developed resistance at higher temperatures, becoming extremely resistant at 25 °C. On account of the sensitiveness of this rust to high temperatures it seems improbable that it will ever become thoroughly established in Manitoba and Saskatchewan, as in these two provinces the summer temperature is probably too high to permit its development.
THE EFFECT OF FERMENTATION ON SOME PROPERTIES OF GLUTEN
Authors: Guest G. H. , Larmour R. K.
Published: April 2011

Except in the cases of a flour of unusually high protein content (19%) and a Pacific Club wheat flour of 7.6% protein, the loss of gluten protein after four hours' fermentation was about 17% and the change in water-holding capacity was negligible. There was practically no differentiation between flours from heavily frosted wheat and average sound flours. The 19% protein flour, however, showed a loss of gluten protein of only 5 % and a slight increase in water-holding capacity; the Club flour showed a loss of 43.4% in gluten protein and a decrease of 27% in water-holding capacity. It is concluded that these two properties of gluten cannot be used to differentiate most flours.
FROST-HARDENING STUDIES WITH LIVING CELLS: II. PERMEABILITY IN RELATION TO FROST RESISTANCE AND THE SEASONAL CYCLE
Authors: Levitt J. , Scarth G. W.
Published: April 2011

Cell permeability as estimated by the plasmolytic method in various types of plants and for different classes of solute has been studied in relation to frost resistance and the seasonal cycle. Permeability is found to increase greatly with hardening, whether induced by low temperature or other conditions, and it seems to parallel closely the seasonal changes in frost resistance. As regards different species and varieties, cell permeability in the hardened state shows better correlation than any other character with ability to resist frost. The permeability change is greatest towards potassium nitrate—at least in cells (viz., those of hardy woody plants) that are definitely permeable to the salt; the change is more moderate towards polar non-electrolytes with small molecules, such as urea, but with these it occurs in all plants capable of hardening; towards apolar substances, such as urethane, there is no change. These relations point to a widening of the aqueous pores or increased hydration of the plasma membrane as the mechanism of the permeability increase. Hypotheses are put forward as to the means by which freer permeability to water may increase resistance to certain types of mechanical injury by frost.
BLACK CHAFF, A COMPOSITE DISEASE
Authors: Hagborg W. A. F.
Published: April 2011

A study was made of the etiology of wheat discolorations that resembled bacterial black chaff. Three distinct types were found. One of these was caused by Phyt. translucens f.sp. undulosum, the bacterial black chaff organism; another yielded Alternaria consistently on isolation; and a third, internodal melanism, appeared to be physiological in origin. Phytomonas alrofaciens was occasionally present in bacterial black chaff lesions.Seed and seedling inoculation methods, unaccompanied by wounding, proved unsatisfactory for testing the pathogenicity of bacterial isolates derived from lesioned wheat plants, but inoculation accompanied by wounding of the young primary leaf, still enclosed in the coleoptile, proved to be a quick and effective method. Soil inoculation methods were ineffective. A method, involving a minimum of mechanical injury to the tissues, was developed for flooding the mesophyll of wheat leaves with a bacterial suspension.
STUDIES ON THE INTERFERTILITY OF FOUR STRAINS OF PUCCINIA HELIANTHI SCHW.
Authors: Brown A. M.
Published: April 2011

A distinct strain of Puccinia Helianthi was collected on each of the following four species, Helianthus annuus, H. petiolaris, H. tuberosus, and H. subtuberosus. All possible combinations of reciprocal crosses, haploid pustule with haploid pustule, and haploid pustule with diploid pustule, were made among these four strains. Interfertile strains, when crossed, give rise to aecia in the formerly haploid pustules. On this basis, the strains fell into two groups: A, the strains on H. annuus and H. petiolaris, and B, the strains on H. tuberosus and H. subtuberosus. The two strains in each group were highly interfertile; but the two strains of one group were highly intersterile with the two strains of the other group. A parallelism exists between the crossing behavior of certain varieties of P. graminis and that of these two groups. It is suggested that each of these two groups of P. Helianthi may represent a variety.
STATISTICAL SIGNIFICANCE OF WHEAT PROTEIN PERCENTAGE DIFFERENCES IN VARIETAL TRIALS
Authors: Whiteside A. G. O.
Published: April 2011

The results of protein determinations on 28 varieties of spring wheat grown in quadruplicate rod-row plots at each of three Dominion Experimental Stations were analyzed statistically. The error due to plot variability greatly exceeded the laboratory error. No real differences were found between the calculated percentages for composite samples made up from the four plots of each station and the percentages obtained by averaging the results from the individual plots.Some of the varieties showed definite tendencies towards high protein content. The major environmental effects of station and of replication gave negative correlations between yield and protein content but when these major factors together with the influence of variety were removed, yield and protein content were not correlated.
PASTURE STUDIES XI. PASTURE RESEARCH IN QUEBEC. CHEMICAL, ECOLOGICAL AND NUTRITIONAL PHASES
Authors: Raymond L. C.
Published: April 2011

Surveys of pasture flora in Quebec have led to the recognition of four layers, viz., turf, tall herbaceous, shrub and tree. The human factor is advanced as the most important single agency determining the existing plant life but water supply and the fertility level exert important effects.The soils under investigation carry sufficient seed to produce, on the average, 77 million potential plants per acre, but these seeds show a low correlation with the plants prevalent in the sward. It was revealed that each mature cow voids [Formula: see text] million viable seeds per grazing season and that these seeds are closely related to the components of the sward.Where phosphorus was applied as superphosphate at a rate of 700 lb. per acre, it was shown that most of that element was fixed in the top half-inch of soil and that the available portion of it was largely depleted after three crop years. Pot cultures of pasture soils growing either Phleum pratense or Trifolium repens show that calcium has depressed and sulphur has increased both the herbage yield and the uptake of phosphorus. The organic fraction of phosphorus in soils has been identified as containing 0.5% of lecithin and 65% of nucleic acid. The latter has been extracted quantitatively in pure form.Mixed herbage and pure grass species have been fed to rabbits as a means of determining feeding value. The 35 groups fed have given highly variable results. Statistical examination of the data shows little if any correlation between gains and the constituents of the herbage as determined by a standard feeding-stuffs analysis. It has been tentatively concluded that the condition of the fibre, depending on the proportion of ligno and hemicellulose, is the most likely cause of the variability. The study is proceeding.
VARIETAL TESTING FOR THE REACTION OF OATS TO DISEASES, ESPECIALLY COVERED SMUT
Authors: Aamodt O. S. , Platt A. W.
Published: April 2011

Artificial inoculation of oat varieties was carried on for a period of five years. Sixty-one varieties of oats were tested in replicated plots for two years and thirteen for three years with a composite collection of inoculum of the covered smut organism, Ustilago levis (Kell. and Swingle) Mag. All gradations in reaction from high susceptibility to apparent immunity were found to exist.Dehulling the kernels previous to inoculation increased the incidence of smut approximately six times. Susceptible varieties gave relatively greater increases in smut when dehulled than did resistant varieties. The increase in smut obtained by dehulling was independent of the year in which the test was conducted.There were no significant differences in the total amount of smut obtained between any two of the seasons in which the tests were conducted but the season influenced the relative varietal reaction.Natural epidemics of halo-blight (Pseudomonas corona-faciens (Ch. Elliott) Stev.) and blast (cause unknown) provided opportunities for obtaining data on the reaction of a large number of oat varieties. Immunity from neither of these diseases was observed but marked varietal differences were noted.
SPERMATOCYTE CHIASMA FREQUENCY IN STRAINS OF MICE DIFFERING IN SUSCEPTIBILITY OR RESISTANCE TO THE SPONTANEOUS OCCURRENCE OF MALIGNANT TUMORS
Authors: Huskins C. Leonard , Hearne E. Marie
Published: April 2011

Significant differences have been found in the spermatocyte chiasma frequencies of ten strains of mice differing in genetic susceptibility or resistance to the spontaneous occurrence of malignant tumors. In three resistant and five susceptible strains there is a positive correlation between susceptibility and low chiasma frequency, and between resistance and high frequency. Two interrelated strains may be exceptional, but their cancer and leukemia records are not clearly established, and one of them, though classed as resistant, is somewhat anomalous genetically.The study comprises a total of 16 tests, each made on 25 complete cells. It was made as an indirect test of a working hypothesis on the mechanism of genetic susceptibility. This hypothesis is based on: (a) the assumed validity of the somatic cell mutation theory of cancer in its most general formulation, (b) the conclusion that gross chromosome irregularities commonly found in tumor cells cannot in themselves be the cause of cancer, though they may be a direct result of some less obvious lack of correlation in the mitotic process, (c) the fact that in different organisms the existence of genes controlling chromosome structure and behavior and other aspects of cell division has been established, (d) the observation that in tumors themselves the chromosomes are commonly found to be "split" precociously, and (e) the observation that "splitting" of meiotic chromosomes is correlated with the absence of chiasma formation. The hypothesis postulated that in strains of mice genetically susceptible to the spontaneous occurrence of tumors, though not yet having cancer, the chromosomes might be found to be "split" slightly in advance of the normal period, and that this could be measured indirectly, but most precisely, by its anticipated effect of causing lowered chiasma frequency at meiosis. The precocious "splitting" would itself be a primary result of some genic difference in the constitution of susceptible animals and might either—through causing grosser chromosome irregularities—lead directly to neoplastic growth, or be a primary morphological concomitant of an underlying cause common to both phenomena.
TETRAMERES CRAMI SWALES, 1933, A NEMATODE PARASITE OF DUCKS IN CANADA.: MORPHOLOGICAL AND BIOLOGICAL STUDIES
Authors: Swales W. E.
Published: April 2011

The male of Tetrameres crami is described and the female is redescribed in the light of further studies. The life history has been elucidated and the larval stages described. Two fresh-water amphipods, Gammarus fasciatus Say and Hyalella knickerbockeri (Bate) are intermediate hosts. A list of definitive hosts, notes on the ecology of the intermediate hosts and on tetrameriasis crami, are included.
NOTE ON THE ACCELERATION OF SHIPS
Authors: Tupper K. F.
Published: April 2011

Calculations were made of the time and distance required for a ship to accelerate to any fraction of its maximum speed, and are intended to serve as a guide in determining the length of run to be made in approaching the measured course in the conduct of ship speed trials. The effect of inaccuracy in the underlying assumptions was examined. Curves and tables are presented and offered as suitable for use.
THE SCATTERING OF X-RAYS AT VERY SMALL ANGLES
Authors: Penley H. H. , Gray J. A.
Published: April 2011

The scattering of X-rays at small angles (minutes of arc) in commercial samples of charcoal and powdered graphite and in anthracene precipitate was investigated. In addition, the effect of pressure on the scattering in Shawinigan charcoal was determined. An absorption method, which is described, was used and the results are shown graphically in the accompanying figure.
PROBABILITY EXPERIMENTALLY INVESTIGATED
Authors: Clark A. L.
Published: April 2011

This paper is the third and last of a series of papers on an experimental investigation on probability. Steel balls were dropped on a horizontal steel plate in which holes were bored in a regular pattern. The probability that a ball will pass through a hole without touching the plate is calculated from the known data and found to be 0.3554 ± 0.0005. The experimental value of the probability or the ratio of free passages to the total number of balls dropped is 0.35557. The agreement is very good. The numbers of runs of various lengths were calculated and compared with the actual numbers of these runs, again with good agreement. π may be calculated from the experimental value of the probability.
THE VISCOSITY OF VINYL ACETATE
Authors: White D. O. , Cuthbertson A. C.
Published: April 2011

The viscosity of monomeric vinyl acetate has been measured over a range of temperatures from 0° to 60 °C. Two equations were obtained which represent the results. The empirical equation is [Formula: see text], and a theoretical equation is given as [Formula: see text]. The characteristic frequency has been obtained from the relation [Formula: see text], where μ is the ratio between the latent heat of evaporation and the heat of cohesion, v was found to be 2.17 × 1012.