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Petrography Of Two Iowa Loess Materials, F. Leicester Cuthbert Jan 1939

Petrography Of Two Iowa Loess Materials, F. Leicester Cuthbert

Proceedings of the Iowa Academy of Science

A research project, in the Department of Geology at Iowa State College, has as its purpose the investigation of the petrography of Iowa clays and soils. The investigation, at present, is concerned with two loess, subgrade materials which behave differently as roadbeds but are similar as far as ordinary physical tests are concerned. The samples are being subjected to fractionation by a supercentrifuge, complete chemical analyses, X-ray analyses, microscopic study and base exchange determinations. Work, to date, suggests that the colloidal portions of the two materials differ in their mineralogical character; one apparently containing as its principle clay mineral, illite, …

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A Bovine Monstra Duplica, Karl A. Stiles, Collis M. Spencer Jan 1939

A Bovine Monstra Duplica, Karl A. Stiles, Collis M. Spencer

Proceedings of the Iowa Academy of Science

Double monsters are pathological deviants from identical twins, in that the embryos are joined in some manner. The embryos may be symmetrically united and developed, or one of the individuals may he arrested in its development. In describing the morphological relationships of the calf of this study, the right and left sides will refer to the animal's right and left respectively. From a superficial examination of this specimen it appears to be a single-bodied calf with two heads, an extra leg with two hooves protruding from the hack a short distance caudal to the vertex of the two heads, and …

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The Biological Action Of Rotenone On The Lake Fauna, Howard L. Hamilton Jan 1939

The Biological Action Of Rotenone On The Lake Fauna, Howard L. Hamilton

Proceedings of the Iowa Academy of Science

The powdered root of Derris elliptica, which contains the alkaloid, rotenone, has long been used by the natives of tropical countries as a fish and arrow poison. Recently it has been introduced in this country as an insecticide, and is being used by conservation workers to remove rough fish from waters which are to be stocked with game fish. Little or no consideration has been given to the possibility that the poison might kill other members of a lake fauna (thus breaking the food chain) and seriously affect the survival of any fish with which the waters might he restocked. …

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The Time Of Embryonic Determination Of Sensoria And Antennal Color, And Their Relation To The Determination Of Wings, Ocelli And Wing Muscles In Aphids, Karl A. Stiles Jan 1939

The Time Of Embryonic Determination Of Sensoria And Antennal Color, And Their Relation To The Determination Of Wings, Ocelli And Wing Muscles In Aphids, Karl A. Stiles

Proceedings of the Iowa Academy of Science

Intermediate-winged aphids of the species Macrosiphum solanifolii were studied in an effort to determine the time of embryonic segregation of the sensoria and antennal color, and their relation to the determination of wings, ocelli, and wing muscle. Dark antennal color and increased sensoria of winged aphids are considered to be characters closely correlated in development; for in general, when there was a darkening of antennae, there was a corresponding increase in the number of sensoria. In practically all cases increased sensoria were correlated with a relatively large amount of nondegenerate wing muscle. It is concluded that embryonic determination of dark …

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The Address Of The President: The Chromosome And The Origin Of Species, J. N. Martin Jan 1939

The Address Of The President: The Chromosome And The Origin Of Species, J. N. Martin

Proceedings of the Iowa Academy of Science

In Lamark's Philosophy of Zoology published in 1809 and devoted to the author's views on the origin of species there is the following statement: The most important of the laws, methods, and progress of nature have nearly always sprung from the examination of the smallest objects which she contains and from apparently the most insignificant enquiries. The studies of chromosomes, nuclear bodies so minute that they escaped discovery until recently but now considered the primum mobile of nearly all life processes, have well verified the truth of Lamark's statement. That the chromosomes, insignificant in sizes as they are, constitute the …

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Reports: Executive Committee; Secretary; Treasurer; Staff Reports; Committee Reports Jan 1939

Reports: Executive Committee; Secretary; Treasurer; Staff Reports; Committee Reports

Proceedings of the Iowa Academy of Science

No abstract provided.

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Cytoplasmic Structures In The Basidium Revealed By Silver Impregnation, J. E. Sass Jan 1939

Cytoplasmic Structures In The Basidium Revealed By Silver Impregnation, J. E. Sass

Proceedings of the Iowa Academy of Science

Basidia of Coprinus fimetarius treated by silver impregnation methods exhibit blackened bodies in the cytoplasm. The size, shape, position and distribution of these bodies correspond to those of bodies demonstrated by mitochondrial techniques. The silver-absorbing bodies in the basidium are unlike the Golgi bodies demonstrated in some animal cells by silver impregnation, but bear much resemblance to mitochondria.

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Further Evidence Of A New Factor In The B Complex, W. R. Wyatt, V. E. Nelson Jan 1939

Further Evidence Of A New Factor In The B Complex, W. R. Wyatt, V. E. Nelson

Proceedings of the Iowa Academy of Science

The vitamin B complex is generally accepted as containing at least five distinct components for the rat; B1 (thiamin), flavin, nicotinic acid, B6, and the filtrate factor. Work by Jukes and Babcock (1) and by Oleson and co-workers (2) indicates that a distinct antiparalytic factor (very likely Reader's "B4") exists. Stocks tad (3) has reported a growth factor "U" for the chick. One of the authors (4) has given evidence of the existence of still another factor, the "8B factor," in the B complex. That chondroitin sulfuric acid is a growth factor for the rat …

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Fossils Of The Peorian Loess In Iowa, Cornelia Cameron Jan 1939

Fossils Of The Peorian Loess In Iowa, Cornelia Cameron

Proceedings of the Iowa Academy of Science

The fossils of representative sections of Peorian loess in Iowa have been examined in detail for the purpose of determining the conditions under which the loess was deposited. In most cases samples were collected at six inch intervals. The shells, pulmonate gastropods, were washed, identified, and charted in order of their vertical occurrence. The majority of species have equivalent modern forms whose habitats are known. Assuming that their mode of living was approximately the same as in the period of loess deposition, ecological conclusions may be drawn. Each section gives a history of local change of moist and dry conditions …

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The Use Of "Keys" In Teaching Biological Classification, H. E. Jaques Jan 1939

The Use Of "Keys" In Teaching Biological Classification, H. E. Jaques

Proceedings of the Iowa Academy of Science

Patagonia would doubtlessly prove thrilling to the biologist if he were only there. When far-distant lands are put out of reach, what can be better than to emphasize the biology of our own immediate locality and that is much more practical for our students. Two fields of interest are brought to our high school and college classes. Some of our students desire a knowledge of biology to use in a professional way. Very often a much larger percentage of the enrollment will never enter any purely biological vocation, hut all may acquire an interest in the common plants and animals …

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Parasitology In The High School Curriculum, Elery R. Becker Jan 1939

Parasitology In The High School Curriculum, Elery R. Becker

Proceedings of the Iowa Academy of Science

In his retiring address to the American Society of Parasitologists, Dr. F. C. Bishop (1938) made the following plea: "I believe there is need for a textbook on parasitology suitable for grade and high school students, and that this society might well take the initiative in getting included in the curriculum of every high school in this country an elementary course in a subject which touches, often in a vital way, the life of every individual." Shall the schoolmen oi Iowa take his plea seriously? Residents of the temperate zone are inclined to refer matters of parasitological interest to mankind …

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Teaching The Scientific Method In General Zoology At The College Level, Karl A. Stiles Jan 1939

Teaching The Scientific Method In General Zoology At The College Level, Karl A. Stiles

Proceedings of the Iowa Academy of Science

Science teachers generally consider teaching the scientific method as one of their chief objectives in a general course. But too often after setting up this objective they leave it. The most widely used textbook of zoology in the Midwest is Hegner's General Zoology and yet there is not one word in this popular text on the scientific method. Two of the newest texts of zoology are Textbook of Zoology by Potter, and Animals without Backbones by Buchsbaum. These books have received much favorable comment yet Buchsbaum's does not contain one word about the scientific method and Potter's devotes about one …

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A Key To Species Of Cyclops In Iowa, Malcolm Mcdonald Jan 1939

A Key To Species Of Cyclops In Iowa, Malcolm Mcdonald

Proceedings of the Iowa Academy of Science

The genus Cyclops is one of the most common of the m1crocrustacea, and it occurs in almost every body of fresh water. Apparently because of this universality it has developed a wide variety of species and forms which are very difficult to distinguish from each other. For any study of ecological or geographical distribution of the genus, specimens must be identified as to species and subspecies. As an aid to such studies the following key has been compiled. This is not a field key in the sense that it can be used for field identification, but it will serve for …

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Influence On Oocyst Production Of Concentration And Kind Of Yeast In Rations Of Rats Infected With Eimeria Nieschulzi, Philip C. Waters Jan 1939

Influence On Oocyst Production Of Concentration And Kind Of Yeast In Rations Of Rats Infected With Eimeria Nieschulzi, Philip C. Waters

Proceedings of the Iowa Academy of Science

Previous investigators have shown that a liberal supplement of yeast induces higher production of oocysts during an immunizing infection with Eimeria nieschulzi than either certain other supplements or complete lack of supplement. The question arises, however, whether lesser amounts of yeast would result in lower oocyst yields, and conversely, greater amounts in higher yields. Furthermore, because of the seeming association of the substance that produced the conditions requisite for higher oocyst counts with vitamin G, and sometimes B also, it was evident that a study with two strains of yeast differing in comparative content of vitamins B and G would …

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The Temperature Cycle In The Okoboji Lakes, Theodore L. Jahn, A. B. Taylor Jan 1939

The Temperature Cycle In The Okoboji Lakes, Theodore L. Jahn, A. B. Taylor

Proceedings of the Iowa Academy of Science

For the past thirty years members of the staff of the Iowa Lakeside Laboratory have been interested in the flora and fauna of the Okoboji region. For a somewhat shorter period of time, whenever equipment has been available, studies have been made of the physical and chemical characteristics of the Okoboji Lakes in the hope of obtaining a better understanding of the environmental factors which affect the biological productivity of these bodies of water. The factors which determine the geographical distribution of any given species and the numbers of individuals of that species which are present at any given time …

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Some Observations On The Habits Of The Thirteen-Lined Ground Squirrels, Citellus Tridecemlineatus Tridecemlineatus (Mitchill) Of Iowa, Gow M. Bush Jan 1939

Some Observations On The Habits Of The Thirteen-Lined Ground Squirrels, Citellus Tridecemlineatus Tridecemlineatus (Mitchill) Of Iowa, Gow M. Bush

Proceedings of the Iowa Academy of Science

A number of thirteen-lined ground squirrels, Citellus tridecemlineatus tridecemlincatus, Mitchill were collected from September through November at the Golf Course of the State University of Iowa. Their habits were observed both in the field and in the laboratory, and recorded. It is hoped that these data will not only be of interest but will supplement some of the information already available.

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The Effects Of Homologous Carbamates On The Respiratory Metabolism Of Blocked And Active Embryos, Guy M. Everett Jan 1939

The Effects Of Homologous Carbamates On The Respiratory Metabolism Of Blocked And Active Embryos, Guy M. Everett

Proceedings of the Iowa Academy of Science

The effects of ethyl, n-propyl, and n-butyl carbamate on the respiration of blocked (diapause) and active (postdiapause) grasshopper embryos have been studied. The three compounds are essentially similar in their narcotic action. The oxygen consumption of active embryos is depressed approximately 50 per cent (to the diapause level) by 0.25 M ethyl carbamate or 0.025 M n-butyl carbamate. The blocked embryo is depressed only 10 per cent. The rates of oxygen consumption expressed as cu. mm. oxygen per embryo per hour for morphologically similar blocked and active embryos show that concentrations up to 0.025 M n-butyl carbamate have a slight …

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Absorption Of Light In The Okoboji Lakes, A. B. Taylor, Theodore Louis Jahn Jan 1939

Absorption Of Light In The Okoboji Lakes, A. B. Taylor, Theodore Louis Jahn

Proceedings of the Iowa Academy of Science

In August 1938 the absorption of light was measured at various depths in the Okoboji Lakes by means of a photronic cell and a tungsten filament lamp which were mounted behind glass windows in separate metal housings so that a parallel beam of light passed through one half meter of water before striking the photronic cell. This apparatus could be lowered to any desired depth, and the transmission at that depth could be measured with a microammeter. This was converted to percentage transmission through one meter by comparison with a similar reading taken with the apparatus in air. After the …

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Writers And Banana Trees, Edwin C. Kepler Nov 1938

Writers And Banana Trees, Edwin C. Kepler

Purple Pen

No abstract provided.

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The Apple Tree, Evangeline French Nov 1938

The Apple Tree, Evangeline French

Purple Pen

No abstract provided.

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Two-Fold Autumn, W. Wendell Phillips Nov 1938

Two-Fold Autumn, W. Wendell Phillips

Purple Pen

No abstract provided.

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The Alumnus, V22n3, July 1938, Iowa State Teachers College Jul 1938

The Alumnus, V22n3, July 1938, Iowa State Teachers College

The Alumnus

Inside This Issue:
-- Cry of Anguish Comes from China to T.C. Mother
-- President O.R. Latham
-- "The Obligations of a Teachers College"
-- Honor Badges Awarded at Fifty-Eighth Reunion
-- Panther Prowl
-- A Campus Surveys its Religious Program
-- S.A. Lynch Delivers Baccalaureate Address
-- Alumni Office Visitors
-- Faculty Activities
-- Alumni News
-- Marriages
-- Births
-- Deaths
-- Alumni Calendar of Events

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Iowa State Teachers College Program Of Recitations, Fall/Winter/Spring 1937-38, Iowa State Teachers College Apr 1938

Iowa State Teachers College Program Of Recitations, Fall/Winter/Spring 1937-38, Iowa State Teachers College

UNI Schedule of Classes

A listing and schedule of the courses being taught as well as policies and procedures concerning attending classes at the Iowa State Teachers College.

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The Alumnus, V22n2, April 1938, Iowa State Teachers College Apr 1938

The Alumnus, V22n2, April 1938, Iowa State Teachers College

The Alumnus

Inside This Issue:
-- Teachers College Travels the Road to Mandalay
-- He That Runs May Read
-- Choric Speaking Comes to Teachers College
-- from the Bureau of Alumni Affairs
-- Men, Did He Say? There Were Bedbugs, too!
-- Trackmen to Challenge Reign of the Nodaks
-- Crack of Bats, Smack of Baseballs - It's Spring
-- Surest Signs of Spring
-- Spring Football Practice Awaits Only Firm Sod
-- Here's Your Ballot!
-- Faculty Scholarship
-- Alumni News, Marriages, Births, Deaths
-- A Schedule of Coming Events

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My First Job, Margaret Wilkie Feb 1938

My First Job, Margaret Wilkie

Purple Pen

No abstract provided.

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On Approaching The Black Hills, Julia Entz Feb 1938

On Approaching The Black Hills, Julia Entz

Purple Pen

No abstract provided.

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Shakespeare And The Fairies, James L. Gordon Feb 1938

Shakespeare And The Fairies, James L. Gordon

Purple Pen

No abstract provided.

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Science And Society (Academy Address), Charles E. Friley Jan 1938

Science And Society (Academy Address), Charles E. Friley

Proceedings of the Iowa Academy of Science

Two quotations will serve as texts for this brief discourse on Science and Society: The late Dr. Edwin E. Slosson - "In our civilization the mechanical forces have forged ahead of the moral and intellectual forces. Modern man is like the Arab fisherman who liberated from the bottle genii he did not know how to control." Stuart Chase - "This is the last great adventure; the boldest, most exhilarating, most dangerous adventure that ever challenged the intelligence and spirit of mankind. From our brains have sprung a million wild horses, now running loose and almost certain sooner or later to …

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Charts And Pictures As Aids In Teaching Students To Use Identification Keys, H. E. Jacques Jan 1938

Charts And Pictures As Aids In Teaching Students To Use Identification Keys, H. E. Jacques

Proceedings of the Iowa Academy of Science

To do any task well, aims and purposes need to be clearly defined. The application of Biology, like many other subjects, is two-fold; professional and cultural. The majority of the students pursuing biological studies in our schools will never make a direct application of this knowledge in a professional way. On the other hand, cultural ideas secured from the field prove just as valuable to the professional biologist as to those who are interested only in broadening their experiences. Cultural interests for all, plus technical excellence for the minority who plan to make definite use of biology in their life …

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Late Fall And Winter Bird Records, 1930 To 1938, In The Upper Missouri Valley, Wilfred D. Crabb Jan 1938

Late Fall And Winter Bird Records, 1930 To 1938, In The Upper Missouri Valley, Wilfred D. Crabb

Proceedings of the Iowa Academy of Science

These records are brought together and intended to be a continuation of the winter bird lists of the Upper Missouri Valley, started in 1916 by T. C. Stephens. Dr. Stephens compiled a series of papers during the period of 1916-22,1 after which time Chas. ]. Spiker, then of Sioux City, covered the winter periods from 1922 to 1926.2 Wm. Youngworth published another summary of winter records from 1926 to 1930. 3 The present paper begins at the end of that period. Other papers of this series have taken into account the physical features of this region. Therefore, the …

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