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Notes On Some Of The Rarer Birds Of The Ames Region, H. E. Ewing Jan 1922

Notes On Some Of The Rarer Birds Of The Ames Region, H. E. Ewing

Proceedings of the Iowa Academy of Science

While the writer was living at Ames during several past years he took various notes on birds observed in that vicinity. During the years 1917, 1918, 1919 and 1920, regular excursions were taken, sometimes alone, sometimes accompanied with other bird enthusiasts and sometimes with his college students in bird study. It was only during the year 1919 that the writer taught the course in bird study for the Department of Zoology at the Iowa State College. While this course was taught by Professor H. A. Scullen and later by Professor J. E. Guthrie, the writer frequently accompanied the classes on …


Nest-Digging And Egg-Laying Habits Of Bell's Turtle, Frank A. Stromsten Jan 1922

Nest-Digging And Egg-Laying Habits Of Bell's Turtle, Frank A. Stromsten

Proceedings of the Iowa Academy of Science

During the summer of 1921 some forty or fifty Bell's turtles dug their nests on the side of a small hill just north of the Iowa Lakeside Laboratory. This afforded an excellent opportunity for the study of the nest-digging and egg-laying habits of this species of turtle. When the turtle is digging her nest or depositing her eggs she is not easily frightened so that it is possible to get very close to the animal and to use a flash light within an inch or two of the body. On several occasions a number of students at the Laboratory were …


Chance In Development As A Cause Of Variation, P. W. Whiting Jan 1922

Chance In Development As A Cause Of Variation, P. W. Whiting

Proceedings of the Iowa Academy of Science

Variation is ordinarily considered as due to internal hereditary factors interacting with external environmental factors during development. In experimental work with a parasitic wasp considerable variation has been found in certain pure-bred stocks kept at certain constant environmental conditions. Either at other constant environmental conditions or in other pure-bred stocks this variation does not occur. Variation appearing under uniform conditions of heredity and environment is considered as due to slight irregularities of division and distribution of cells during embryology and to other more or less intangible factors of development. Individual variation resulting from chance in development is on the average …


Submarginal Venation Of Foliage Leaves, Robert B. Wylie Jan 1922

Submarginal Venation Of Foliage Leaves, Robert B. Wylie

Proceedings of the Iowa Academy of Science

An earlier paper gave a brief account of experiments dealing with the conductive efficiency of certain types of vein systems in foliage leaves. By cutting the blade in various ways it was possible to show some of the advantages and also the disadvantages of different types of venation. The results indicated that larger veins, while highly efficient for conduction along their length, may constitute real barriers to movement across them, especially when interrupted by breaks in the veins, which cuts doubtless lead to leakage. On the other hand, regions free from larger veins showed marked capacity for conduction in all …


Some Wound Responses Of Foliage Leaves, Robert B. Wylie Jan 1922

Some Wound Responses Of Foliage Leaves, Robert B. Wylie

Proceedings of the Iowa Academy of Science

The leaves of plants are their most exposed organs. The thin summer foliage of herbaceous plants and deciduous trees generally suffers so severely that one rarely finds an uninjured leaf. While the degree of wounding is less serious in the evergreens, since they are tougher and offer greater resistance, lesions are not uncommon on these especially on the broader leaved evergreens. The plant's ability, therefore, to deal with such frequent accidents must be highly developed to meet these daily needs for renewed cortex.


Germination Studies Of Some Shrubs And Trees, L. H. Pammel, C. M. King Jan 1922

Germination Studies Of Some Shrubs And Trees, L. H. Pammel, C. M. King

Proceedings of the Iowa Academy of Science

A study has been made by the Botanical Department of Iowa State College during the past season of the germination of the following: Quercus Gambellii, Pasania densiflora, Maclura pomifera, Prunus caroliniana, Rhus Toxicodendron, Rhus canadensis, Gleditsia aquatica, Rhamnus californica, Rhamnus tinctoria, Lycium halimiflorum and Shepherdia argentea.


The Species Of Rhamnus In Southwestern United States And The Pacific Coast And Puccinia Coronata, L. H. Pammel Jan 1922

The Species Of Rhamnus In Southwestern United States And The Pacific Coast And Puccinia Coronata, L. H. Pammel

Proceedings of the Iowa Academy of Science

Brewer and Watson in the Botany of California list four species and one variety of the genus Rhamnus in California as follows: Rhamnus alnifolia, R. crocea, R. californica and var. tomentella and R. Purshiana. Jepson in his Flora of Western Middle California lists three species and two varieties, the only addition to that of the flora of California being the variety ilicifolia. Trelease in his revision of North American Rhamnus records the following species and three varieties of Rhamnus of Western United States: Rhamnus crocea Nutt and var. pilosa, R. alnifolia, R. Purshiana, …


Description And Key Of The Genus Cucurbita, Fred C. Werkenthin Jan 1922

Description And Key Of The Genus Cucurbita, Fred C. Werkenthin

Proceedings of the Iowa Academy of Science

J. H. Trumbull, in a letter quoted in Bull. Torrey Bot. Club, Vol. 6:69-70; 1876, states, "I could never discover where the doubt came in, as to the American origin of several well-known varieties of these gourds, or Millions as some call them, or Pompions as I may call them. In England, the name 'squash' was understood to be of American origin. Robert Boyle mentions his experiment with the seed of 'squash' which is an Indian kind of pompion that grows apace." "Beverley (History of Virginia, 124) describes the Macocks as 'a sort of Melopepones, or lesser sort of …


The Founders Of The Art Of Plant Breeding, Fred C. Werkenthin Jan 1922

The Founders Of The Art Of Plant Breeding, Fred C. Werkenthin

Proceedings of the Iowa Academy of Science

The paper by Prof. Werkenthin on History of Plant Breeding was one of the assigned topics in the course given at Iowa State College on the History of Botany. The subject matter is so admirably treated that it has seemed wise to publish this as a posthumous paper. It was the last paper prepared by him, finished only a few weeks before he was taken sick.


Studies Of Insect Transmission And Cross Inoculation Of Mosaic On The Solanaceae, Cucurbitaceae And Leguminosea, O. H. Elmer Jan 1922

Studies Of Insect Transmission And Cross Inoculation Of Mosaic On The Solanaceae, Cucurbitaceae And Leguminosea, O. H. Elmer

Proceedings of the Iowa Academy of Science

The results of most investigators tend to show that the mosaic disease is quite limited in its host range. Recent experiments show that such is probably not the case.


A Comparative Study Of The Red-Seeded And Common Dandelion, June Berry Jan 1922

A Comparative Study Of The Red-Seeded And Common Dandelion, June Berry

Proceedings of the Iowa Academy of Science

To the casual observer the dandelions which prove so serious a pest in lawns and elsewhere, appear to be of only one species. Upon closer investigation, it is found that there are two common species, the Common Dandelion, Taraxacum taraxacum (L) and the Red-seeded Dandelion, Taraxacum erythrospermum (Andrz). These two species are the most easily distinguished by their seeds which are an olive brown and dark red color respectively.


A Manual Of The Ferns And "Fern-Allies" Of Grinnell And Vicinity, Henry S. Conard Jan 1922

A Manual Of The Ferns And "Fern-Allies" Of Grinnell And Vicinity, Henry S. Conard

Proceedings of the Iowa Academy of Science

The writer believes that for every floristic district of the State there should be a simple and convenient manual of the local flora. As a first attempt to meet this need, the following manual is presented. The other vascular plants should be similarly covered.


The Structure And Development Of The Seed Coat And Cause Of Delayed Germination In Mellilotus Alba, J. N. Martin Jan 1922

The Structure And Development Of The Seed Coat And Cause Of Delayed Germination In Mellilotus Alba, J. N. Martin

Proceedings of the Iowa Academy of Science

The epidermis of the ovules forms the much elongated cells, known as the Malpighian cells of the seed coat. The outer walls of the Malpighian cells are much thickened and are composed of layers differing in physical properties. One of these layers is the light line which in most seeds is impervious to water until it is modified by weathering or by some artificial means. The light line is apparently only more compact cellulose for it hydrates quickly in water at 80° C. and then gives a distinct cellulose reaction and is permeable to water. The action of the weather …


Effect Of Hardness Of Water On The Fungicidal Value Of Mercuric Chloride Solutions, J. C. Gilman Jan 1922

Effect Of Hardness Of Water On The Fungicidal Value Of Mercuric Chloride Solutions, J. C. Gilman

Proceedings of the Iowa Academy of Science

A comparison of the fungicidal value of mercuric chloride solutions made up in tap water with those made up in distilled water showed that the tap water solutions were much less effective in killing the sclerotia of Rhizoctonia solani on potato tubers. Of the 182 sclerotia treated with bichloride, 1-1000 in distilled water, only 6 or 1.1 per cent grew. In the case of a similar treatment of tap water solution of the 139 sclerotia examined, 34 or 7.1 per cent grew. Ninety per cent of untreated sclerotia grew in the control experiments. These facts are important in the application …


Dolomites From The Austrian Tyrol And Other Localities, Nicholas Knight Jan 1922

Dolomites From The Austrian Tyrol And Other Localities, Nicholas Knight

Proceedings of the Iowa Academy of Science

Deodat Dolomieu was born in Dolomieu, France, June 23, 1750, and died November 16, 1801. In infancy he was created a Knight of Malta. He seemed precocious in many directions. When nineteen years of age he quarreled with a companion and killed him. He was condemned to death for the crime, but after nine months' imprisonment, he was pardoned on account of his, youth: He early became interested in geology and mineralogy, and wrote some important treatises on his favorite subjects, especially while residing in Metz, the interesting old capital of Lorraine.


Electrometric Titration Of Sulfurous Acid With Permanganate, W. S. Hendrixson, L. M. Verbeck Jan 1922

Electrometric Titration Of Sulfurous Acid With Permanganate, W. S. Hendrixson, L. M. Verbeck

Proceedings of the Iowa Academy of Science

The purpose of this work was to determine whether sulfurous acid in acid solution is completely oxidized to sulfuric acid by an excess of permanganate as stated in the literature. If so the excess of permanganate should be easily and accurately determinable electrometrically with potassium iodide thus giving a simple method for determining sulfur dioxide, sulfurous acid or sulfites. The results show that with a small or large excess of permanganate only about 90 per cent is oxidized to sulfuric acid, the remainder of the sulfurous acid probably forming dithionic acid.


The Electrometric Standardizing Of Titanous Solutions, W. S. Hendrixson, L. M. Verbeck Jan 1922

The Electrometric Standardizing Of Titanous Solutions, W. S. Hendrixson, L. M. Verbeck

Proceedings of the Iowa Academy of Science

The great value of titanous salts in analytical chemistry has become well known through the work of many chemists. Titanous chloride has been used in determining not only inorganic but also many organic substances, which are likely to be colored or to give colored solution on reduction, thus interfering in the accurate determination of end-points in the usual methods of analysis where colored indicators are used. Such difficulties would, of course, be removed by the application of the voltage method. Moreover, so intensely reducing is the titanous ion that an interval of nearly one volt is given between a slight …


Studies Of Yeast V - Is Bios A Single Substance, Ellis I. Fulmer, V. E. Nelson Jan 1922

Studies Of Yeast V - Is Bios A Single Substance, Ellis I. Fulmer, V. E. Nelson

Proceedings of the Iowa Academy of Science

In previous communication (Journal of Biological Chemistry, March, 1922) Fulmer and Nelson showed that the water extract of alfalfa is much richer in the yeast growth stimulant, Bois, than is the 95 per cent alcoholic extract of the same material. In the work here described two extracts were prepared as follows from alfalfa which had been previously extracted with ether. Extract A was an extract by long extraction with absolute alcohol. Extract B was an extract prepared by long extraction of the absolute-alcohol-extracted material with water. Both extracts showed optimum concentrations for maximum stimulation and were about equally potent. Combinations …


Index Jan 1922

Index

Proceedings of the Iowa Academy of Science

No abstract provided.


Fall Term Commencement [Program], November 29, 1921, Iowa State Teachers College Nov 1921

Fall Term Commencement [Program], November 29, 1921, Iowa State Teachers College

UNI Commencement Programs

The program of the commencement ceremonies, including a list of institutional leadership, a list of the departments by college, awards given at the ceremonies, and a list of undergraduate and graduate degree candidates.


The Alumni News Letter, V5n4, October 1, 1921, Iowa State Teachers College Oct 1921

The Alumni News Letter, V5n4, October 1, 1921, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.


Summer Term Commencement [Program], August 18, 1921, Iowa State Teachers College Aug 1921

Summer Term Commencement [Program], August 18, 1921, Iowa State Teachers College

UNI Commencement Programs

The program of the commencement ceremonies, including a list of institutional leadership, a list of the departments by college, awards given at the ceremonies, and a list of undergraduate and graduate degree candidates.


The Alumni News Letter, V5n3, July 1, 1921, Iowa State Teachers College Jul 1921

The Alumni News Letter, V5n3, July 1, 1921, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.


Spring Term Commencement [Program], May 31, 1921, Iowa State Teachers College May 1921

Spring Term Commencement [Program], May 31, 1921, Iowa State Teachers College

UNI Commencement Programs

The program of the commencement ceremonies, including a list of institutional leadership, a list of the departments by college, awards given at the ceremonies, and a list of undergraduate and graduate degree candidates.


The Alumni News Letter, V5n2, April 1, 1921, Iowa State Teachers College Apr 1921

The Alumni News Letter, V5n2, April 1, 1921, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.


Winter Term Commencement [Program], March 8, 1921, Iowa State Teachers College Mar 1921

Winter Term Commencement [Program], March 8, 1921, Iowa State Teachers College

UNI Commencement Programs

The program of the commencement ceremonies, including a list of institutional leadership, a list of the departments by college, awards given at the ceremonies, and a list of undergraduate and graduate degree candidates.


Methods Of Teaching Parasitology, Herbert R. Werner Jan 1921

Methods Of Teaching Parasitology, Herbert R. Werner

Proceedings of the Iowa Academy of Science

The fact that animal parasites are important as disease producing agents has been known for a great many years. Thought, consideration, study, and emphasis on the question of parasitism have come in waves; at times it was looked upon as one of the most important factors to be dealt with, while at other times or periods it has received almost no attention and parasites have been looked upon as more or less unimportant as disease producing agents. But the necessity for the protection of our livestock from disease has grown, being governed largely by the supply and demand, together with …


Key To The Families Of Flowering Plants Of Central Iowa, Henry S. Conard, Winifred Ellsworth Jan 1921

Key To The Families Of Flowering Plants Of Central Iowa, Henry S. Conard, Winifred Ellsworth

Proceedings of the Iowa Academy of Science

No abstract provided.


1921 Old Gold, Iowa State Teachers College Jan 1921

1921 Old Gold, Iowa State Teachers College

UNI Yearbooks

The student yearbook of the Iowa State Teachers College, later known as the University of Northern Iowa.


The Alumni News Letter, V5n1, January 1, 1921, Iowa State Teachers College Jan 1921

The Alumni News Letter, V5n1, January 1, 1921, Iowa State Teachers College

The Alumni News Letter

Contains news of the College and its alumni.