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An Upper Silurian Vertebrate Horizon, George M. Robertson Jan 1950

An Upper Silurian Vertebrate Horizon, George M. Robertson

Proceedings of the Iowa Academy of Science

The earliest fossil fragments which have been positively identified as vertebrate come from the Upper Ordovician. They are fragments, the best known of which come from the Harding sandstone near Canon City, Colorado. Though fragmentary, study of the histological structure of the plates indicates that they were bony, therefore vertebrate, and that the bone structure agrees with that in the shields of the Heterostraci, one of the orders of Ostracoderms. (1) These are intriguing fragments, hints of the presence of vertebrates but inadequate to give us any idea of the body form or of any details of structure. · Following …

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Effect Of Shock On Performance In A Paired-Associate Learning Task, Eli Saltz Jan 1950

Effect Of Shock On Performance In A Paired-Associate Learning Task, Eli Saltz

Proceedings of the Iowa Academy of Science

Hullian psychology conceptualizes the effects of noxious stimulation as drive producing and the effects of removal of such stimulation as a rewarding state of affairs (3). These effects have been repeatedly demonstrated in situations where they have facilitated learning (2, 4). It is obvious, however, that increased drive need not necessarily aid learning, and it may at times hinder it. The present study is concerned with the consequences for learning when electric shock is introduced at the same time as the stimulus word and is removed when the response word is spoken in paired-associate learning. The study is particularly interested …

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Mortality In Relation To Age In Young White Pekin Ducks With Blood-Induced Plasmodium Lophurae Infection, E. R. Becker Jan 1950

Mortality In Relation To Age In Young White Pekin Ducks With Blood-Induced Plasmodium Lophurae Infection, E. R. Becker

Proceedings of the Iowa Academy of Science

The extreme susceptibility of ducks to Plasinodium lophurae was first reported by Wolfson (1940) who noted both the high parasitemia and mortality that followed blood-inoculation of these birds. The course of the infection in ducklings has been studied by a number of workers, among them Hewitt, Richardson and Seager (1942), Rigdon and Varnadoe (1945), and Becker, Brodine and Clappison (1949), all of whom support Wolfson's findings. Marshall, Litchfield and White (1942) state that over a 4-month period they lost 95.1 % of a total of 205 infected control ducks, the average survival time being 9.3 ± 4 days. Hewitt et …

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Some Effects Of Temperature On The Rates Of Embryonic, Postembryonic And Adult Growth In Hyalella Azteca, Eugene Cleveland Bovee Jan 1950

Some Effects Of Temperature On The Rates Of Embryonic, Postembryonic And Adult Growth In Hyalella Azteca, Eugene Cleveland Bovee

Proceedings of the Iowa Academy of Science

Although it is generally accepted that temperature is one of the more important factors determining the rate of biological processes for invertebrates, much remains to be investigated concerning its effect on growth and development. Amongst the Crustacea are numerous animals for which such an investigation is practicable. One such organism, readily available in almost any freshwater pond and quite easily raised in the laboratory, is the amphipod Hyalella azteca.

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Intranasal Newcastle Disease Virus Vaccination Of Baby Chicks Infected With Ascaridia Galli, O. H. Peterson, K. B. Kerr Jan 1950

Intranasal Newcastle Disease Virus Vaccination Of Baby Chicks Infected With Ascaridia Galli, O. H. Peterson, K. B. Kerr

Proceedings of the Iowa Academy of Science

An acute infectious disease of poultry manifested by both respiratory and nervous symptoms which occurred in the Dutch East Indies was first described by Kraneveld in 1926 (1 & 2). Shortly thereafter, the disease was observed at Newcastle-on-Tyne in England by Doyle (3) who gave it its present name. In California, Beach (4) described a respiratory-nervous disorder of chickens which he named Avian Pneumoencephalitis and which (5) later was shown to be identical with the disease described by Kraneveld and by Doyle. The disease has been reported from almost all sections of the world. In 1945, Newcastle disease was first …

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Some Paleoecoloical Speculations Regarding The Earliest Vertebrates, George M. Robertson Jan 1950

Some Paleoecoloical Speculations Regarding The Earliest Vertebrates, George M. Robertson

Proceedings of the Iowa Academy of Science

Vertebrate paleontology concerns itself mainly with bones. Seldom is there any fossilized remnant of other structures. Vertebrate paleoecology has a task like that of Ezekiel, to "make those dry bones live," to try to reconstruct from the data available the habitat, the mode of life, and the associations of these creatures of the past. Unfortunately we are seldom able to accomplish our task by Ezekiel's method of "prophesying." There is call for a good play of imagination in the task and sometimes it is difficult to draw a line between what we like to call "scientific imagination" and the garden …

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Home Range Of The Southern Woodchuck, Richard F. Trump Jan 1950

Home Range Of The Southern Woodchuck, Richard F. Trump

Proceedings of the Iowa Academy of Science

In this study of the home range of the woodchuck, Marmota monax monax (L), the mammals were live-trapped and marked with metal ear tags. Data from 65 catches of 47 specimens in Van Buren County, 1940-1941, from the writer's Master of Science thesis (Iowa State College, 1943), along with data from 58 catches of 24 specimens in Story County, 1946-1949, are incorporated in this report.

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A Prelilninary List Of The Calliphorinae (Diptera) Known To Occur In Iowa, Carl M. Yoshimoto, D. D. Millspaugh Jan 1950

A Prelilninary List Of The Calliphorinae (Diptera) Known To Occur In Iowa, Carl M. Yoshimoto, D. D. Millspaugh

Proceedings of the Iowa Academy of Science

The typical bluebottle and greenbottle flies are one of the five subfamilies under the family Calliphoridae. They are generally known as the blowflies. The subfamilies are classified chiefly on the bases of the bristles on their thorax. Other characteristics are provided for substantial clarification.

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The Effect Of Thiouracil On The Golgi Apparatus Of The Thyroid Gland In The White Rat, Ralph H. Shepherd Dec 1949

The Effect Of Thiouracil On The Golgi Apparatus Of The Thyroid Gland In The White Rat, Ralph H. Shepherd

Proceedings of the Iowa Academy of Science

Thiouracil, a heterocyclic derivative of thiourea related to pyrimidine, has been found to have certain goitrogenic effects as well as various other bodily effects on laboratory animals treated with the substance. The goitrogenic effects are inhibition of active thyroid hormone formation and a stimulation of gland growth. Inhibition of hormone formation is believed to be due to the combination of thiouracil with iodine (Miller, Roblin, and Astwood, 1945), and, as has been suggested, the drug may act as an antivitamin or antibiotic, since its toxic reactions are similar to those of sulfanilamide, another antivitamin (Laufer and Stewart, 1947). Stimulation of …

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Iowa State Teachers College Schedule Of Classes, Fall 1949, Iowa State Teachers College Oct 1949

Iowa State Teachers College Schedule Of Classes, Fall 1949, 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 Red And The White, James V. Hatch Feb 1949

The Red And The White, James V. Hatch

Purple Pen

No abstract provided.

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In Memoriam - William A. Anderson; Norval Baker; Jacob Corwin Blumer; William Harold Davis; E. W. Lindstrom; W. H. Mcfarland; Thomas C. Stephens; Charles S. Trachsel; Emery Ernest Watson Jan 1949

In Memoriam - William A. Anderson; Norval Baker; Jacob Corwin Blumer; William Harold Davis; E. W. Lindstrom; W. H. Mcfarland; Thomas C. Stephens; Charles S. Trachsel; Emery Ernest Watson

Proceedings of the Iowa Academy of Science

No abstract provided.

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Some Contributions Of Fossil Study To The Problem Of Vertebrate Origin, George M. Robertson Jan 1949

Some Contributions Of Fossil Study To The Problem Of Vertebrate Origin, George M. Robertson

Proceedings of the Iowa Academy of Science

Prior to Darwin's time there had been speculations regarding the origin and the relationships of the various plant and animal groups. Some of these were ingenious and some of them hit close enough to post-Darwinian ideas to have led some biologists to over-value them. To most biologists of those days, however, such problems were unimportant. They seem to have taken the animal and plant groups for granted. Similarities and differences were used in classification, but to their authors such concepts as archetypes, etc. probably had no special philosophic importance. A vertebrate archetype was like an alphabet, a composite of the …

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A Fish Population Study Of Storm Lake, Earl T. Rose Jan 1949

A Fish Population Study Of Storm Lake, Earl T. Rose

Proceedings of the Iowa Academy of Science

Storm Lake, in Buena Vista County, is one of Iowa's largest inland bodies of water, covering a total of 3,060 acres. It is relatively shallow, with an average depth of about 6 feet, exclusive of a small dredged area along the east shore. The water in the lake is seldom clear due to wave action and heavy blooms of blue-green algae during summer. Spring and fall water conditions are usually good, and in recent years fishing has been excellent during these periods. The present game fish populations have been developed primarily by natural reproduction of indigenous species, and to a …

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A Preliminary List Of The Dytiscidae Known To Occur In Iowa, J. C. Schaffner, H. E. Jaques Jan 1949

A Preliminary List Of The Dytiscidae Known To Occur In Iowa, J. C. Schaffner, H. E. Jaques

Proceedings of the Iowa Academy of Science

These predacious diving beetles constitute the largest family (Dytiscidae) of Coleoptera inhabiting water. They are often seen hanging head downward in the water with the tip of the abdomen exposed at the surface. The members of this family are rather oval and flattened in shape. The elytra are usually hard and shiny, often with many punctures. Some of the smaller species are pubescent. The bare filiform antennae are glabrous and have eleven segments. The hind legs are flattened and have five tarsal segments which are fringed with long hairs making them strongly adapted for swimming. The beetles are usually brownish …

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Iowa State Teachers College Schedule Of Classes, Winter 1948-1949, Iowa State Teachers College Jan 1949

Iowa State Teachers College Schedule Of Classes, Winter 1948-1949, 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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Minutes & Reports - Executive Committee; Business Meeting; Secretary; Treasurer; Staff Reports; Committee Reports Jan 1949

Minutes & Reports - Executive Committee; Business Meeting; Secretary; Treasurer; Staff Reports; Committee Reports

Proceedings of the Iowa Academy of Science

No abstract provided.

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What An Academy Can Do To Promote The Conservation Of Natural Resources, J. M. Aikman Jan 1949

What An Academy Can Do To Promote The Conservation Of Natural Resources, J. M. Aikman

Proceedings of the Iowa Academy of Science

Modern man is not a builder. On the contrary he is an exploiter. He depends on natural resources, directly or with minor adaptation and modification, for his material needs. Likewise, he draws upon natural resources for thousands of things in which he takes special delight: things he sees, hears, smells, tastes, touches and feels. All of these natural resources are being cut down, torn down, shot down, burned, plowed up, washed away, blown away, and generally wasted and destroyed. Conservation of natural resources is inconsistent with utilization or use by man. If we use them we no longer have them …

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Science Changes Its Mind, W. H. Kadesch Jan 1949

Science Changes Its Mind, W. H. Kadesch

Proceedings of the Iowa Academy of Science

In an interesting book bearing the title "Architects of Ideas" Trattner tells us that "in every age previous to our own there was supposed to exist a body of knowledge final and infallible. Frequently people thought of this knowledge as having been revealed directly from heaven. Embodied in rigid tradition and held sacred by all authorities, it was considered heresy to question any time-honored belief." The great development in human culture that Mees has called the Helix of History began somewhere in the eastern hemisphere five or six millennia ago. For many centuries advancement was slow. Succeeding turns of the …

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Considerations Involved In The Management Of Prairie Reserves, Ada Hayden, J. M. Aikman Jan 1949

Considerations Involved In The Management Of Prairie Reserves, Ada Hayden, J. M. Aikman

Proceedings of the Iowa Academy of Science

Iowa is known as a prairie state yet native grassland is not generally recognized by Iowans, for the virgin prairie which originally covered five-sixths of the state has been largely removed by the mechanics of farming, and only the characteristic soil profile of the prairie remains to mark its boundaries. The few scattered tracts of prairie which still persist as parts of undivided estates have been the source of the two state-owned reserves. According to a projected plan of the state Conservation Commission others will be acquired, where possible, representing various soil associations and climatic variations.

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A Study Of The Cardinal In Iowa, James Hodges Jan 1949

A Study Of The Cardinal In Iowa, James Hodges

Proceedings of the Iowa Academy of Science

One of the newer birds in the state of Iowa during the last half century is the Eastern Cardinal Richmondena cardinalis cardinalis. The Cardinal is a Carolinian form but has extended its range through most, if not all, of Iowa and has been recorded as a breeding bird in Minnesota and other northern states. This study was conducted from the spring of 1943 through October, 1947 in the area of Scott County, Iowa where the Cardinal is now a common resident. The Cardinal, because of its striking plumage, has attracted the attention of even the non-bird student and thus has …

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Revisions And Additions To Our List Of Iowa Corixidae, D. D. Millspaugh Jan 1949

Revisions And Additions To Our List Of Iowa Corixidae, D. D. Millspaugh

Proceedings of the Iowa Academy of Science

A preliminary survey and ecological notes of Iowa Corixidae was submitted to the Iowa Academy in 1940 in which paper some eight species were included. Since that time a monograph of the Corixidae of the Western Hemisphere by Dr. H. B. Hungerford, which includes a monograph of the Trichocorixa by Dr. R. I. Sailer, has been published. This work makes the present paper seem warranted and necessary since their study makes many generic changes as well as adds much to the known species.

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A Preliminary List Of The Hydrophilidae Known To Occur In Iowa, S. S. Statler, H. E. Jaques Jan 1949

A Preliminary List Of The Hydrophilidae Known To Occur In Iowa, S. S. Statler, H. E. Jaques

Proceedings of the Iowa Academy of Science

The Hydrophilidae, or water scavenger beetles, received their name from the genus Hydrophilus, a word of Greek origin meaning, "a lover of water." They are usually found in ponds and streams. Several genera are, however, terrestrial in habit, living in moist earth and in the dung of cattle and horses, where they are said to feed upon the larvae of dipterous insects. The family consists of some 1,700 species, mostly tropical, but well represented in the temperate regions. About 190 species are known from the United States.

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Notes On Ant-Lions, Richard F. Trump Jan 1949

Notes On Ant-Lions, Richard F. Trump

Proceedings of the Iowa Academy of Science

In April 1944, while stationed with the Navy along Manzanillo Bay in Panama I became interested in the ant-lions which "den" in the dust under the coconut trees. In order to observe their digging operations I captured three and placed them in a tin can partly filled with dust. Watching them excavate their deadly pits, I noticed how perfectly spaced the holes were for use of the available space.

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The Alumnus, V32n4, October 1948, Iowa State Teachers College Oct 1948

The Alumnus, V32n4, October 1948, Iowa State Teachers College

The Alumnus

Inside This Issue:
-- Fall Activities Calendar
-- The Campus Today
-- Honor Memory of Dean Reed, Prof. Watson
-- Long-Term Faculty Members Retire
-- Teachers College Has Changes In Faculty
-- Leeman Wins Silver Medal in Olympics
-- The Panther Parade
-- College Announces Plans for New Campus School
-- Concert Season Opens October 9
-- Mobile Unit Brings Industrial Arts to Rural Schools
-- Newest Contributors to Chapel Fund
-- Keeping Up with Alumni
-- Marriages
-- Births
-- Deaths

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Iowa State Teachers College Schedule Of Classes, Fall 1948, Iowa State Teachers College Oct 1948

Iowa State Teachers College Schedule Of Classes, Fall 1948, 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 College Eye And Pen, May 1948 [Download Entire Issue] May 1948

The College Eye And Pen, May 1948 [Download Entire Issue]

Purple Pen

No abstract provided.

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And The Dawn Broke Clear, Ralph Salisbury May 1948

And The Dawn Broke Clear, Ralph Salisbury

Purple Pen

No abstract provided.

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Iowa State Teachers College Schedule Of Classes, Spring 1948, Iowa State Teachers College Apr 1948

Iowa State Teachers College Schedule Of Classes, Spring 1948, 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 Leeches Of The Okoboji Region, Carol Kenneth Mathers Jan 1948

The Leeches Of The Okoboji Region, Carol Kenneth Mathers

Proceedings of the Iowa Academy of Science

Mullin (1926) in an unpublished thesis has listed 20 species of leeches found in the Okoboji Region. During the summers of 1946 and 1947 the writer has found two additional species so that the list now includes the following.

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