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The Propagation Of The Bluegill, Helioperca Machrochria (Rafinesque), And The Black Crappie, Pomoxis Spariodes (Lacepede) In Iowa Gravel Pits, Everett B. Speaker Jan 1936

The Propagation Of The Bluegill, Helioperca Machrochria (Rafinesque), And The Black Crappie, Pomoxis Spariodes (Lacepede) In Iowa Gravel Pits, Everett B. Speaker

Proceedings of the Iowa Academy of Science

The purpose of this paper is to discuss the value of abandoned gravel pits in Iowa for the propagation of bluegill, Helioperca machrochira, and black crappie, Pomoxis spariodes. These observations were made at the Lake View fisheries station, located in Sac County. This area formerly constituted a series of thirty pits varying in size from a fraction of an acre to five acres. Several years ago the Iowa Fisheries Division stocked a number of fishes in one of the pools to ascertain their value for fish production. A marked degree of success attended their efforts, and an elaborate plan of …

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The Order Of Embryonic Determination Of Several Organs In Macrosiphum Solanifolii, K. A. Stiles Jan 1936

The Order Of Embryonic Determination Of Several Organs In Macrosiphum Solanifolii, K. A. Stiles

Proceedings of the Iowa Academy of Science

Aphids in nature are normally either winged or wingless. However, it has been found that there also occur individuals which are intermediate in wing development: that is to say, some individuals have only partly formed wings and therefore are intermediate between the winged and wingless types. The production of large numbers of intermediate-winged aphids can be induced in the laboratory by artificial means such as certain combinations of light and temperature.

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Pathological Polyploidy In Seedlings Of Corn And Sorghum, J. E. Sass Jan 1936

Pathological Polyploidy In Seedlings Of Corn And Sorghum, J. E. Sass

Proceedings of the Iowa Academy of Science

The writer had demonstrated that Coprinus sterquilinus contains an extra-nuclear mechanism which bears structural homologies with the Golgi apparatus in animal spermatocytes. Numerous other Hymenomycetes have been examined. Coprinus atramentarius contains a distinct Nebenkern sphere, consisting of a large hyaline sphere, in which there are peripheral, chromophilic granules. This body is most distinct just before the meiotic division of the fusion nucleus occurs. It is probable that the sterigmatic bodies described by various workers, are derived from this Golgi apparatus, rather than from the centrosomes.

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The Rossi-Cholodny Technic As An Aid In The Study Of The Decomposition Of Lignin, H. H. Mollenhoff, F. B. Smith, P. E. Brown Jan 1936

The Rossi-Cholodny Technic As An Aid In The Study Of The Decomposition Of Lignin, H. H. Mollenhoff, F. B. Smith, P. E. Brown

Proceedings of the Iowa Academy of Science

The study of the soil microflora by direct microscopic examination offers the possibility of observing the activities of the microorganisms in their natural surroundings and the attention of soil microbiologists has been directed along this line from time to time. Rossi (4) and Cholodny (1) working independently proposed similar methods which yield results of a qualitative nature and their methods have come to be known as the Rossi-Cholodny technic. Recently, Conn (2 and 3), Winogradsky (6), and Ziemiecka (7) have contributed to the further development of the method, adapting it to laboratory conditions.

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A Factor In The Distribution Of Minor Veins In Dicotyledon Leaves, Robert B. Wylie Jan 1936

A Factor In The Distribution Of Minor Veins In Dicotyledon Leaves, Robert B. Wylie

Proceedings of the Iowa Academy of Science

Critical survey of a wide series of foliage leaves shows a fairly close relation between mesopyll organization and intervascular distance. Among Dicotyledons there is a close correlation between relative amount of leaf tissue that is horizontally arranged in the blade in comparison with that having cells elongated at right angles to the epidermis.

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Green Plants And The Reactions Of Iron, Norman Ashwell Clark Jan 1936

Green Plants And The Reactions Of Iron, Norman Ashwell Clark

Proceedings of the Iowa Academy of Science

In several of its aspects the problem of the availability of iron for plants is still unsolved. If the problem is not unique, it is at least unusual. In general, the plant takes its elements in simple combinations - almost, the simpler the better. Phosphorus is picked up as phosphate, nitrogen as nitrate or ammonia, sulphur as sulphate, and metals can be given as salts - nitrates, sulphates and chlorides. But try putting ferric chloride into a nutrient solution with a reaction around the neutral point! The plant turns yellow; the leaves become chlorotic, and there are all the indications …

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The Presence Of A "Nebenkern" In Coprinus Atramentarius, J. E. Sass Jan 1936

The Presence Of A "Nebenkern" In Coprinus Atramentarius, J. E. Sass

Proceedings of the Iowa Academy of Science

The writer had demonstrated that Coprinus sterquilinus contains an extra-nuclear mechanism which bears structural homologies with the Golgi apparatus in animal spermatocytes. Numerous other Hymenomycetes have been examined. Coprinus atramentarius contains a distinct Nebenkern sphere, consisting of a large hyaline sphere, in which there are peripheral, chromophilic granules. This body is most distinct just before the meiotic division of the fusion nucleus occurs. It is probable that the sterigmatic bodies described by various workers, are derived from this Golgi apparatus, rather than from the centrosomes.

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Some Notes On The Religion Of The Indians, Albert B. Reagan Jan 1936

Some Notes On The Religion Of The Indians, Albert B. Reagan

Proceedings of the Iowa Academy of Science

To a great extent religion determines the advancement that any people makes, and the Indian was no exception in this connection. The writer wishes to explain that he is to deal only with our Indians as found by the Europeans following the discovery by Columbus, and hence is not called on to consider or discuss the claims of the higher systems of religion, and consequently all special questions, such as, the inspiration and infallibility of the Bible, are entirely foreign to his purpose. He is here presenting the facts as found by him and other scientists, leaving the conclusions for …

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In Memoriam: Charles Sherman Cobb; Elbert William Rockwood; Franklin Scott Wilkins; Alonzo A. Miller; James H. Lees, T. C. Stephens, J. N. Pearce, H. D. Hughes, W. A. Hauber, E. J. Cable Jan 1936

In Memoriam: Charles Sherman Cobb; Elbert William Rockwood; Franklin Scott Wilkins; Alonzo A. Miller; James H. Lees, T. C. Stephens, J. N. Pearce, H. D. Hughes, W. A. Hauber, E. J. Cable

Proceedings of the Iowa Academy of Science

No abstract provided.

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A Genetic Study Of The Vibrato, Alan D. Grinsted Jan 1936

A Genetic Study Of The Vibrato, Alan D. Grinsted

Proceedings of the Iowa Academy of Science

The question of whether or not the vibrato, which is found in the singing voice of all vocal artists and of some untrained adults, and occasionally in the speaking voice, is learned, or is due to some inborn physiological characteristic is one which has been the subject of considerable speculation. Upon this question rest the answers to such questions as these: Will there come a day when voices with vibrato will not be considered beautiful? Should the vibrato be expected to appear automatically when a student of singing learns to vocalize properly or is there a special technique to be …

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A Study Of Drouth Recovery, And Seasonal Succession In A Pond (Preliminary Study), Malcolm Mcdonald Jan 1936

A Study Of Drouth Recovery, And Seasonal Succession In A Pond (Preliminary Study), Malcolm Mcdonald

Proceedings of the Iowa Academy of Science

A study was made comparing the fauna and flora of a southeastern Iowa pond during the years 1933 to 1935, inclusive; that is during a complete cycle from conditions of abundance of rain and ground water to a very arid condition of drouth and then back again. With this was combined a study of the development and change in fauna during the period from March to June, 1935.

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Relation Of Light To The Growth And Movement Of Plants (Address To The Academy), William J. Robbins Jan 1936

Relation Of Light To The Growth And Movement Of Plants (Address To The Academy), William J. Robbins

Proceedings of the Iowa Academy of Science

At the meetings of the American Association for the Advancement of Science held at St. Louis last Christmas, the $1000 prize for the most outstanding paper presented at the meetings was awarded to Dr. P. W. Zimmerman and Dr. A. E. Hitchcock of the Boyce Thompson Institute. The paper for which they received the prize dealt with the results of their experiments on the effect of various chemical substances on the local initiation of adventitous roots on stems and leaves, proliferation, the swelling and bending of stems, the acceleration of growth and epinasty. Certain chemical substances including ß indoleacetic acid, …

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Officers, Committees, Past Presidents, And Members, Iowa Academy Of Science Jan 1936

Officers, Committees, Past Presidents, And Members, Iowa Academy Of Science

Proceedings of the Iowa Academy of Science

No abstract provided.

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Inheritance Of Resistance And Susceptibility To Salmonella Aertrycke In Mice, H. O. Hetzer Jan 1936

Inheritance Of Resistance And Susceptibility To Salmonella Aertrycke In Mice, H. O. Hetzer

Proceedings of the Iowa Academy of Science

In previous reports by the writer and others it has been shown that the resistance of a strain of mice to controlled infections of Salmonella acrtrycke could be greatly increased by selective breeding. After fourteen generations of selection for resistance to a standard close of 2 x 105 organisms the mortality in the selected stock (S) was only 8 per cent as compared with a mortality of approximately 98 per cent in the highly susceptible Silver (Sil) and Bagg albino (Ba) strains.

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The Address Of The President: Paul Bunyan Turns Scientist, R. E. Buchanan Jan 1936

The Address Of The President: Paul Bunyan Turns Scientist, R. E. Buchanan

Proceedings of the Iowa Academy of Science

Paul Bunyan Turns Scientist-Paul Bunyan, the legendary hero of the north woods has in recent years developed far toward becoming the Baron Munchausen of America. In fact, his feats of strength and cleverness quite surpass those of the Baron himself.

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Research Vs. Conservation, W. W. Aitken Jan 1936

Research Vs. Conservation, W. W. Aitken

Proceedings of the Iowa Academy of Science

Conservation defined, means to supervise and protect. The supervising and protecting of wild life requires a knowledge of life history, habits, and daily activity of the particular objects under observation. This information is only gained after study and research into all factors effecting the life of plant and animal.

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Studies On Sporobolomyces And Bullera, H. C. Olson Jan 1936

Studies On Sporobolomyces And Bullera, H. C. Olson

Proceedings of the Iowa Academy of Science

Thirty-two cultures of spore-discharging false yeasts were isolated from the air and from other sources examined. Detailed studies identified twenty-six of the cultures as members of the genus Sporobolomyces and the remaining six as members of the genus Bullera. Twelve of the cultures of Sporobolomyces were classified as S. salmonicolor, eleven as S. roseus and the remaining three cultures apparently constitute a new species. The six cultures of Bullera were all identified as B. alba. Considerable variation was noted among the cultures of each species of Sporobolomyces and Bullera but, since marked variations in a culture could be induced by …

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Studies On The Removal Of Fluorine From Drinking Waters In The State Of Iowa, C. A. Kempf, W. E. Galligan, D. A. Greenwood, V. E. Nelson Jan 1936

Studies On The Removal Of Fluorine From Drinking Waters In The State Of Iowa, C. A. Kempf, W. E. Galligan, D. A. Greenwood, V. E. Nelson

Proceedings of the Iowa Academy of Science

Our knowledge concerning the distribution of fluorine in drinking waters and the effect of such waters on the structure of the teeth has been appreciably expanded by the recent researches of Smith, Lantz, and Smith (1), Churchill (2), McKay (3), Kehr (4), Ostrem, Nelson, Greenwood, and Wilhelm (5), Boissevain (6), Dean (7), Sebrell, Dean, Elvove, and Breaux (8) and Boruff and Abbott (9). Smith, Lantz, and Smith (1), of the University of Arizona, were the first to show that mottled enamel is clue to fluorides in the drinking water; in fact, their analyses of waters from endemic areas show that …

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The Effects Of Fluorides On The Teeth, C. A. Kempf, V. E. Nelson Jan 1936

The Effects Of Fluorides On The Teeth, C. A. Kempf, V. E. Nelson

Proceedings of the Iowa Academy of Science

Mention was made, in the previous paper, of the fact that mottled enamel of the teeth results from the presence of fluorine in the water supply. The water of the city of Ankeny and surrounding territory may have a fluorine concentration to exceed eight or ten parts per million of water; mottled enamel is very prevalent in that area. Work by Smith (1) of the University of Arizona indicates that mottled enamel may result when the concentration of fluorine is as low as 0.8 to 0.9 part per million of water. The work of Schulz and Lamb (2) and McCollum, …

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Comparative Anatomy In The Small School, Fae M. Shawhan Jan 1936

Comparative Anatomy In The Small School, Fae M. Shawhan

Proceedings of the Iowa Academy of Science

We have been using for about eight years at Drake University, a plan in presenting our course in comparative anatomy which we think has been very successful. It is a plan which will work most efficiently in smaller schools, schools where the number in comparative anatomy laboratories does not exceed fifteen people, but some phases of it can be applied to the larger class.

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The Responses Of Normal And Castrate Female Sparrows To Injections Of Pregnant Mare Serum, Richard Avery Miller Jan 1936

The Responses Of Normal And Castrate Female Sparrows To Injections Of Pregnant Mare Serum, Richard Avery Miller

Proceedings of the Iowa Academy of Science

During the winter months, ovaries and oviducts of the sparrows are greatly reduced. Injection of pregnant mare serum during this resting period stimulates the ovary to an activity which simulates that of the breeding season. Oviducts respond to the increased amounts of female hormone released by the ovary.

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A Stain On Erin's Honor, Mary A. Sheridan Nov 1935

A Stain On Erin's Honor, Mary A. Sheridan

Purple Pen

No abstract provided.

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The Purple Pen, Volume 8, Number 1, November 1935 [Download Entire Issue] Nov 1935

The Purple Pen, Volume 8, Number 1, November 1935 [Download Entire Issue]

Purple Pen

No abstract provided.

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Christmas Among The Indians, Delaine Kellogg Nov 1935

Christmas Among The Indians, Delaine Kellogg

Purple Pen

No abstract provided.

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The Purple Pen, Volume 7, Number 3, May 1935 [Download Entire Issue] May 1935

The Purple Pen, Volume 7, Number 3, May 1935 [Download Entire Issue]

Purple Pen

No abstract provided.

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The Watchman, T. A. Lamke May 1935

The Watchman, T. A. Lamke

Purple Pen

No abstract provided.

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Iowa State Teachers College Program Of Recitations, Winter 1934-1935, Iowa State Teachers College Jan 1935

Iowa State Teachers College Program Of Recitations, Winter 1934-1935, 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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A Preliminary List Of The Neuroptera Of Iowa, H. E. Jaques Jan 1935

A Preliminary List Of The Neuroptera Of Iowa, H. E. Jaques

Proceedings of the Iowa Academy of Science

The Neuroptera or nerve-winged insects represent one of the smaller orders of the great group of six legged animals. No persistent work has been done on this group, for Iowa. The species herein listed have been gotten through general collecting. The list may doubtless be more than doubled by giving special attention to the order. The list is published as a challenge to Iowa nature lovers to find the other species that are doubtless more or less common within our state.

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The Address Of The President: This Changing World, Edward Bartow Jan 1935

The Address Of The President: This Changing World, Edward Bartow

Proceedings of the Iowa Academy of Science

In this address it is my purpose to express some ideas concerning the Changing World of education, science and invention.

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Further Studies On Lactation And Rearing Of Young, J. F. Feaster, Victor E. Nelson Jan 1935

Further Studies On Lactation And Rearing Of Young, J. F. Feaster, Victor E. Nelson

Proceedings of the Iowa Academy of Science

The work performed in this laboratory and elsewhere during the past fifteen years has shown conclusively that a diet adequate for growth may not necessarily fulfill the requirements for lactation. The excellent work of Evans and Bishop (1) has conclusively demonstrated that a specific vitamin is required for reproduction. The fact that lactation is not normal on many synthetic and even natural diets suggests the possibility that all of the factors necessary for normal development are not known. The work in this paper was planned in order to increase our knowledge concerning the nutritional factors involved in milk secretion and …

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