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That the department of chemistry will as- oratory and in preparation. This alone would sign a “fellow," who shall have received his often cut half of the time from the probachelor's degree, to the problem; this fellow fessor's schedule, thus enabling him to improve to devote from half to full time to the prob- his courses by giving them the proper amount lem and the balance to assistant work in the of reflection and applying with deliberation department of chemistry.
the principles of pedagogy. That the fellow shall be paid (about) $800 It will provide a suitable source of outlet per year to be drawn from the “ fellowship” for the research needs of the professor, inasfund and the college funds in proportion to much as he is to be the director of several the amount of time he shall spend on each.' fellowships. The responsibility for their suc
That the work of the fellowship shall be cess will rest primarily upon his shoulders, considered as legitimate material upon recom- although the major portion of the laboratory mendation of the department staff for a work connected with them will be performed thesis for the degree of Master of Science, by others. He will thus have incentive to and in special cases for the degree of Doctor keep“ alive," and the spirit of competition of Philosophy, the fellow having completed and production and contact with the outside the other requisite requirements as of credits, world of industry will make him more keenly languages, residence, etc.
appreciative of his function as a teacher of That (about) 10 per cent. of the fellowship a coming generation of chemists. fund shall be set aside for equipment, chem. The college will be granting advanced icals, traveling expenses, etc.
degrees yearly to its fellows, and these are That the several problems presented shall bound to create a reputation for the college be under the immediate direction of the in their respective fields of investigation department member who represents that which will make for its recognition and branch of the science, or of a director of success. industrial research and head of the division The increase in the department personnel of industrial chemistry.
due to many assistants will decrease the work That the regular salary of each department and responsibility of each professor, thus promember who has fellowships under his super viding the time in which he may study and vision shall be augmented by a specified sum work upon his fellowship problems, and his to be drawn from the fellowship fund. salary will be justly augmented by inspiring
That fellows engaged upon industrial prob- work performed in working hours rather than lems shall not be charged laboratory fees, or by depressing analytical procedures performed breakage fees, nor shall there be any charges at night or at the expense of college courses. relative to their procurement of any ad- He will not then feel the need of an apology vanced degree.
for the profession of his choice. In brief, That department members will not accept the college and its teaching staff in chemistry any personal propositions which might legit- will have much to gain and nothing to lose imately become a department fellowship.
by the adoption of a system of cooperation The scheme as developed should relieve with industry in chemical research much of the aforementioned difficulties and
ROBERT H. BOGUE “ diseases." The higher salary paid assistants would
PITTSBURGH, PA. create a demand and a competition among men for the positions. High-class men may
THE DIGESTIBILITY OF THE BRANNY be selected. These men, being holders of at
COATS OF WHEAT least the bachelor's degree, will be available THERE is one phase of the recurrent subfor assistant work of a high order, such as ject of the digestibility of flours containing will relieve the professors of a vast amount more or less of the branny portion of wheat of responsibility and time spent in the lab- that has not been brought out in the dis
cussion of recent digestion experiments on bran either by Holmes' or Snyder.2
It is a matter of regret that Holmes did not make, or at least did not publish, the proximate analysis of the bran used in his digestion experiments. The bran is merely described as “an ordinary commercial wheat bran secured in the open market.”
For the purpose of this study then we may divide the wheat berry into three portions: The germ or embryo, the branny covering and the flour cells. The branny covering includes several outer and middle layers and the inner layer termed the aleurone layer. The aleurone layer or so-called gluten cells contains proteins apparently in higher amount than the outer layers, but the gluten cells do not possess the properties of, nor take part in the formation of gluten. Hence, although functionally the aleurone layer is a part of the endosperm and serves as a covering for the flour cells or so-called starch cells or floury portion, actually the physical property it possesses of close adherence to the outer coat ings during the milling process, obliges us to consider it as simply one of the bran layers. Neither the bran coats nor the germ contains starch grains or those protein bodies which possess the same characteristics as the crude gluten obtained from the flour cells by the customary mechanical method of washing away the starch from a flour dough. Nevertheless commercial bran as obtained from all processes of milling at present employed contains considerable amounts of starch and gluten. The germ is, for the most part, recovered in the shorts or sometimes as a separate fairly pure product sold as “germ middlings.” Bran manufactured by large wellequipped mills making use of the most improved bran dusting machinery is less "rich" than bran made by the average mill of smaller capacity. In other words, when the bran is closely "skinned” it contains less flour than “rich” bran. The flour present in bran
1 "Experiments on the Digestibility of Wheat Bran in a Diet without Wheat Flour,” U. S. Department of Agriculture. Bulletin No. 751.
2 SCIENCE, N. S., 50, August 8, 1919, pp. 130
exists both as loosely adhering but separate particles and unseparated masses of flour cells. No system of milling, however perfect, is at the present time capable of removing all the floury portions from the bran. Bran contains easily visible specks of flour, both free and adherent. Sometimes millers test the clean-up of their bran by rubbing it upon the coat sleeve or other piece of dark colored cloth. Commercial shorts contains still larger amounts of flour particles. White middlings, “ red dog” and other “rich" feeds contain still more.
One of the tests which the cereal testing laboratory is frequently called upon to perform is the determination of the amount of flour present in bran, shorts and other byproducts of flour milling. The method which we have generally used for this purpose is to determine the percentage of starch. On account of the presence in bran of considerable amounts of pentosans and other carbohydrates, the usual Sacchse method for starch determination is not applicable. The diastase methods is usually used for this purpose. Since wheat four contains on the average about 70 per cent. of starch, the amount of floury material or potential flour present in a wheat by-product may be determined with a fair degree of accuracy by determining the amount of starch and multiplying by one hundred seventieths. Very few samples of bran have as low as 12 per cent. of flour. The average of some recent analyses of commercial brans gave 18.93 per cent. floury material. These may possibly not be representative, but the average amount of floury material in commercial bran will not be far from 15 per cent. and 30 per cent. floury material in commercial shorts is perhaps an average amount.
Consideration of the amounts of flour in average commercial bran will throw a little further light upon the subject of the digestibility of the branny coatings in the human stomach. Bearing in mind then the percentages of digestibility found by Holmes
SU. 8. Dept. of Agriculture, Bureau of Chemistry, Bulletin 107, p. 53.
with ordinary unground wheat bran, viz., for protein 28.0 per cent. and for carbohydrates 55.5 per cent. and the other quoted experiments on graham, whole wheat flours and straight flours where greater or less amounts of the branny coatings were present, it seems perfectly safe to assert that the digestibility of the combined branny coatings of the wheat berry is even lower than the figures quoted. If we may assume, for example, that average commercial bran contains 14 per cent. protein and consists of 15 per cent. flour cells and 85 per cent. branny coats and that average straight flour has 11.5 per cent. protein, 2.1 per cent. of the bran is flour protein and 11.9 per cent. bran protein. If it is fair to apply to the four protein, the average coefficient of protein digestibility-90.9 per cent. found in white flour digestion experiments,* 1.91 per cent. of the bran is digested from the flour protein and since but 3.92 per cent. of the total protein is digested, the balance or 2.01 per cent. represents the digestible protein derived from the bran coats only. The digestibility of the protein of the branny covering of the wheat grain is therefore about 16.8 per cent.
In the absence of data on the digestibility of ground husks and pulverized nut shells, it is perhaps no exaggeration to assert that as far as the digestibility in the human stomach of the branny portion of the wheat grain is concerned, bran must be considered as not much more nutritious or desirable than pulverized nut shells would be.
CHARLES H. BRIGGS THE HOWARD WHEAT AND FLOUR TESTING LABORATORY,
in SCIENCE by Professor Bradley M. Davis and Professor A. Franklin Shull, because the type of course advocated by both is exactly the kind of elementary course that has been given here for nearly twenty years. It is, therefore, extremely gratifying to us to note the tendency that is beginning to manifest itself, as a result of the readjustment from war conditions, in respect to the introductory teaching of botany and zoology in our colleges and universities, and it is our earnest hope that it will not be long before the old type course will have been abandoned everywhere and its place taken by the more significant course based upon fundamental principles.
We have been attempting to do for a long time exactly what Professor Davis expresses as his hope for the future—"nothing more than the grounding of fundamental principles and a selection of information with rather definite reference to its general and practical interests, or its broad philosophical bearing,” and Professor Shull's description of the first course in zoology, as it has been given in the University of Michigan for several years, applies in all essential respects to ours.
In no sense has our introductory course been one based upon the study of types, and never has it been dominated by anatomy. It has been our strong conviction that such a course fails utterly, from an educational point of view, in affording an adequate introduction to the study of zoological science. A thorough study of a single animal and studies in comparative morphology and in taxonomy belong, we have always held, to the more advanced and specialized courses designed for students who have an interest in the further pursuit of zoological knowledge, and not to the introductory course.
Long ago we recognized the obvious fact that the great majority of students who take our course in general zoology will receive no further biological training, and, therefore, our efforts have been directed toward giving it
1 SCIENCE, N. S., Vol. 48, November 22, 1918, pp. 514-515.
2 SCIENCE, N. 8., Vol. 48, December 27, 1918, pp. 648-649.
THE INTRODUCTORY COURSE IN
ZOOLOGY It has been of especial interest to those of us in the University of Missouri who have taken part in the presentation of the introductory course in zoology to read the recent discussion
4 Page 6, U. 8. Dept. of Agriculture, Bulletin No. 751.
significance as a factor in a general education. Throughout the course, the fundamental value of biological science to human welfare is emphasized, and no opportunity is lost to apply biological principles to the life of man. The broad, philosophical bearing of these principles is in no wise impaired by an appeal to prac. tical interests, where such an appeal can be legitimately made.
This is the spirit behind the regulation of our college of arts and science which requires of all its students for graduation the introductory course in either botany or zoology. It seems self-evident to us that a type course does not and can not fulfill such a purpose.
General principles, not phyla and classes, furnish the points d'appui on which we attempt to build up both the lectures and the work of the laboratory. The animals that are used in the laboratory are studied not as representatives of groups, but rather as sample animals, convenient forms for observation and suitable for illustrating principles. Structure is never divorced from function in the instruction, and anatomical facts that fall within the scope of the course are not presented as of interest per se, but only as bearing upon general principles or as having some useful application.
The course is based upon the following fundamental aspects of zoological science, no one of which is unduly emphasized or slighted: (1) The organization of animals, both structural and functional; (2) the relation of animals to their environment, both general and specific (including economic considerations and relation of animals to disease); (3) the origin of the individual; and (4) the relation between successive generations of animals.
The several sections of the class are under the direction of different instructors, and each man is free to work out his own method of presentation of facts and their application to principles, but the final result and the spirit and the purpose of the course are the same throughout, although it may happen that the end is reached by somewhat different methods and arrangements of material.
The following outline, while not attempting to set forth details, fairly well represents the
general scope and nature of our introductory course.
I. INTRODUCTION. Lectures: (1) Definitions; scope and position of zoology among the sciences; historical background of zoological science; (2) fundamental aspects of zoology; (3) protoplasm and its properties; (4) fundamental structure and functions of animals—the cell as the unit of structure and function.
II. THE ORGAN-SYSTEMS AND THEIR FUNCTIONS. (A) Lectures: Based on the laboratory work on the frog, with reference, however, to other forms, including man; foods and the principles of nutrition are emphasized. (B) Laboratory work: The study of the organs of the frog and their functions, with numerous demonstrations and simple experiments. The concept of the animal as a cellular organism, as well as that of cell-differentiation, is built up through a study of tissues, both macerated and in section, of the frog and other animals.
III. RELATIONS TO ENVIRONMENT. (A) Lectures: General ecological relations; adaptations, behavior, etc., with special reference to the frog. (B) Laboratory work: Observations and experiments on the frog and other forms.
IV. THE PROTOZOA. (A) Lectures: General characteristics; structure; functions, including reactions and reproduction; relations to environment; relation to disease. (B) Laboratory work: Study of Ameba, Euglena, Paramecium, Gregarines; observations and experiments to illustrate general principles; demonstrations of pathogenic protozoa and other unicellular organisms.
V. HYDRA. (A) Lectures: The study of Hydra as a simple metazoon and the beginning of cell-differentiation. Reproduction in the Cælenterata. (B) Laboratory work: The study of Hydra and a hydroid colony. Demonstration of other Cælenterates.
VI. INSECTS. (A) Lectures: Structure; life-histories; adaptations; habits and social relations; parasitism; insects as carriers of pathogenic organisms. (B) Laboratory work: The study of the grasshopper, and comparison with representatives of other orders. Numerous demonstrations illustrating protective coloration, mimicry, and other ecological relations. Demonstrations of parasitic insects and other animal parasites, with explanation of relation to hosts.
het. (A) Lectures : Thevelop
ance of an excessf the excess over that of the
eral principles of reproduction and development. (B) Laboratory work: The study of the development of the frog, and comparison with other forms. Demonstrations of mitosis, germcells, chromosomes, fertilization; chick embryos and their nutritive mechanism; mammalian embryos and their relation to the placenta.
VIII. PRINCIPLES OF GENETICS. (A) Lectures: (1) Essentials of Mendelian heredity; (2) mechanism of heredity. (B) Laboratory work: Demonstrations of living and preserved material illustrating Mendelian principles.
IX. PRINCIPLES OF ORGANIC EVOLUTION. (A) Lectures: (1) Sources of evidence for evolutional change; (2) the method of evolution, with brief historical account and a discussion in the light of recent knowledge of the manner in which evolutional change takes place. (B) Laboratory work: Demonstrations of fluctuations, mutations, etc. Demonstrations of paleontological material, both fossils and models.
GEORGE LEFEVRE UNIVERSITY OF MISSOURI,
If one compares the statistics of the years 1917 and 1918, for the seventy-seven departments of which account was taken, one will note that last year shows not only the persistance of an excess of deaths over births, but even an increase of the excess over that of the preceding year. In 1917, the population of the seventy-seven departments not invaded decreased 268,838, whereas the decrease in 1918 has risen to 389,575. This result is due to the considerable increase in the number of deaths during the second half of 1918, ascribable to the influenza epidemic; for the number of births showed a slight increase over 1917. A comparison of the statistics of the years 1917 and 1918 is given in the accompanying table:
.... 399,041 343,310 Deaths
.. 788,616 613,148 Excess of deaths over births .. 389,575 269,838 Marriages
177,872 158,508 Divorces.
..... 8,121 5,572 An analysis of the table reveals the fact that in 1918 there was: (1) an increase in the number of marriages; (2) a corresponding increase in the number of births, and (3) an increase in the number of deaths. This increase in mortality affects exclusively the second half of last year. During the first half of 1918, 316,077 deaths were recorded, as compared with 354,554 during the first half of 1917; and during the second half of 1918, 472,539 deaths were registered, as against 258,594 in 1917. According to the preceding figures, the number of civil victims claimed by the influenza last year may be placed at approximately 200,000.
A PUEBLO RUIN IN NEW MEXICO THREE years ago Earl H. Morris, representing the American Museum of Natural History, undertook the excavation of an ancient Pueblo ruin in Astec, New Mexico. The work was begun at the suggestion and through the courtesy of the H. D. Abrams. the owner of the property, and is being financed from the Archer M. Huntington fund for surveying the southwestern United States. During the past month the museum party has uncovered a new section of the ruin revealing several rooms filled with sand and
SCIENTIFIC EVENTS CHANGES IN THE FRENCH POPULATION IN 1918
The minister of labor has completed the birth and mortality statistics for France for the year 1918. According to the Paris correspondent of the Journal of the American Medical Association the statistics show that the civil population of France decreased during the year 1918 by 389,575, not counting the war losses. The statistics, based on civil records, continue to cover only the seventy-seven departments that were not directly affected by military operations. This is the same as it was during the first four years of the war. It will be the same for the year 1919, and not until the beginning of 1920 will the statistics of all French territory, made complete by accession of Alsace and Lorraine, be included.