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Notes On The Cyperaceae Of Iowa, Herald D. Bennett Jan 1948

Notes On The Cyperaceae Of Iowa, Herald D. Bennett

Proceedings of the Iowa Academy of Science

The information for this paper was obtained from specimens collected by Professor Bohumel Shimek and stored, unidentified except for about 300 specimens, in the herbarium of the State University of Iowa, Iowa City. In the approximately 300 previously identified species just mentioned (the person responsible for their identification is unknown) there were more erroneously than correctly identified plants. A large number of these specimens belonged to the Ovales section and had been identified as Carex festucacea. It was found that there was one Carex festucacea and all the rest were either C. brevior, C. Bicknellii or C. molesta …

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Herbarium Notes, W. A. Anderson Jan 1948

Herbarium Notes, W. A. Anderson

Proceedings of the Iowa Academy of Science

Among many items of interest encountered during the past year in routine work in the Herbarium of the State University of Iowa, the following seem worthy of record. The discovery, in Muscatine County, of n fine colony of Glyceria in the fluitans complex, led to a review of this section of the genus. All of our specimens collected over the past half century had been filed as G. fluitans. The differences between this species and G. septentrionalis Hitchc. seem rather slight yet if we follow actual measurements we must refer all of our eastern Iowa specimens to the latter …

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A Preliminary Report On Biosystematic Studies Of Iowa Smartweeds (Polygonum Spp.), Carl C. Blickenstaff, Charles L. Gilly Jan 1948

A Preliminary Report On Biosystematic Studies Of Iowa Smartweeds (Polygonum Spp.), Carl C. Blickenstaff, Charles L. Gilly

Proceedings of the Iowa Academy of Science

The senior author first developed an interest in the smartweeds (Polygonum spp.) in connection with studies and survey work on the European corn borer (Pyrausta nubilalis Hubn.) and related borers. These are Pyrausta ainsliei Hein, the smartweed borer, and P. penitalis Grote, the lotus borer; both are native to North America, while P. nubilalis was introduced into this country from Europe and has become a serious pest of corn. This insect was first noticed in the United States in 1917 in the New England states. It gradually spread westward and was first reported in Iowa in 1943 from …

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Quantitative Variations Of Stem Tissues During Ontogeny In Tobacco, Robert E. Burns Jan 1948

Quantitative Variations Of Stem Tissues During Ontogeny In Tobacco, Robert E. Burns

Proceedings of the Iowa Academy of Science

Considerable study has been devoted to the ontogeny of tobacco in terms of gross morphology and metabolism. In comparison with the number of such studies we have is yet but few data on the ontogenetic anatomy of this important plant. Consequently it seemed desirable to investigate certain aspects of developmental anatomy characterizing the several distinctive growth stages of tobacco. Since preliminary observations had given some indications that marked variations in stem tissue occurred during growth, an experiment was undertaken to trace these changes throughout the life cycle.

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The Effects Of Paradichlorobenzene On Fungi, Eugene W. Elliott Jan 1948

The Effects Of Paradichlorobenzene On Fungi, Eugene W. Elliott

Proceedings of the Iowa Academy of Science

The need for methods of controlling mite infestations of fungus cultures is felt in every mycological laboratory. Whenever plant or animal material is brought in from the field, there is danger of bringing in also mites or their eggs. If their presence is not recognized in the infested culture and they are not exterminated there, they may pass from culture to culture, mixing and contaminating them all.

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The Effect Of Farm Crops On The Production Of The Ring-Necked Pheasant In Iowa, Lester F. Faber Jan 1948

The Effect Of Farm Crops On The Production Of The Ring-Necked Pheasant In Iowa, Lester F. Faber

Proceedings of the Iowa Academy of Science

A great number of factors have been brought out and used as reasons for the recent decline in populations of the ring-necked pheasant. (Phasianus colchicus torquatus). Research workers are inclined to look for some remote factors that might affect all game populations. Factors that operate over a period of many years perhaps. Are cyclic influences in operation, and do they cause changes in pheasant populations? Are pheasants subject to the fate of many other exotics in that they reach high numbers in areas where they become established only to be followed by a regression in numbers that are never replaced? …

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Preliminary Report On The Flora Of Southeastern Iowa-Part Ii., Charles L. Gilly, Malcolm E. Mcdonald Jan 1948

Preliminary Report On The Flora Of Southeastern Iowa-Part Ii., Charles L. Gilly, Malcolm E. Mcdonald

Proceedings of the Iowa Academy of Science

This paper completes a consideration of the southeastern Iowa specimens in the herbarium of the Parsons College Biology Department. As mentioned in the introductory paragraphs of Part I (Gilly and McDonald 1948), the majority of these specimens were collected by the authors during the years 1933 to 1937; additional collections were made in Jefferson County during the summer of 1946. The Pteridophytes, the single Gymnosperm, the Monocotyledons and the apetalous and polypetalous Dictotyledons were discussed in Part I of this paper. In this second part, a total of 288 species and wellmarked varieties of gamopetalous Dictotyledons, representing the families Monotropaceae …

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Plant Responses To Naturally Emanated Volatile Compounds From Ripe Fruits, Wayne C. Hall Jan 1948

Plant Responses To Naturally Emanated Volatile Compounds From Ripe Fruits, Wayne C. Hall

Proceedings of the Iowa Academy of Science

This work was undertaken in an attempt to demonstrate the effects of natural emanations from fleshy fruits upon various plant organs and to devise a procedure which would be suitable for use as an experiment in an elementary plant physiology course or as a demonstration in general botany.

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The Iowa Lakeside Laboratory - A Prairieless Field Laboratory, Ada Hayden Jan 1948

The Iowa Lakeside Laboratory - A Prairieless Field Laboratory, Ada Hayden

Proceedings of the Iowa Academy of Science

Iowa is a prairie state and thus her institutions and students must wrestle with problems growing out of prairie environment. Slightly more than a hundred years ago, about five-sixths of the state consisted of virgin grassland. For thousands of years the prairie vegetation together with air, weather, and water in the course of time, has been making soil; as season after season, organic matter has been deposited among the particles of pulverized rock. Most of the prairie which lived in centuries past, now lies below the surface of the soil; and with the removal of the sod by cultivation, the …

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A Quarterly Standard Mineral Analysis Of The Waters Of Four Iowa Lakes In The Ruthven Area, Ada Hayden Jan 1948

A Quarterly Standard Mineral Analysis Of The Waters Of Four Iowa Lakes In The Ruthven Area, Ada Hayden

Proceedings of the Iowa Academy of Science

The silt bottomed prairie lakes of Clay and Palo Alto Counties, Iowa, have shallow, hard, alkaline, turbid waters. They are located in the youngest of the glacial drifts, in which the soils are highly calcareous and rich in mineral salts. The more shallow lakes with relatively flat, saucer-like basins, support a rich population of rooted, submerged, and emergent vegetation which minimizes wave action. The lakes whose basins are deeper than four feet are unfavorable to the growth of emergent vegetation and rooted submerged types do not survive the wave action except in the shallow waters along the depositing shores.

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Methods Of A Unialgal Culture Of Pandorina, Clarence Hightshoe Jan 1948

Methods Of A Unialgal Culture Of Pandorina, Clarence Hightshoe

Proceedings of the Iowa Academy of Science

The study of Algae has for many decades’ involved great numbers of very important problems. To try and solve certain phases of these problems, it is first necessary to develop standardized techniques in the handling and culturing of certain forms. It is with this fact in mind that the author has experimented with a controlled set of environmental conditions and a series of culture media for the maintenance in culture, pure and unialgal, of Pandorina morum, a member of the Volvocales.

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The Background And Outlook Of Students Taking Elementary Botany At Iowa Wesleyan College, Phyllis Latta, Jean S. Morrow Jan 1948

The Background And Outlook Of Students Taking Elementary Botany At Iowa Wesleyan College, Phyllis Latta, Jean S. Morrow

Proceedings of the Iowa Academy of Science

Does it help a college student taking botany to have had a course in high school biology? "Why are you taking botany?" That was one of the questions asked a class of forty-two students at Iowa Wesleyan College during their first class meeting of elementary Botany in September of 947. Many indicated that they were taking it to fulfill their eight hour science requirement for graduation, and some of these indicated interest in nature and biology. Twelve out of the forty-two were definitely biology majors or minors.

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A Preliminary Study Of The Liverworts Of Henry County, Iowa, S. S. Statler, Jean Morrow Jan 1948

A Preliminary Study Of The Liverworts Of Henry County, Iowa, S. S. Statler, Jean Morrow

Proceedings of the Iowa Academy of Science

Very few people seem to be familiar with liverworts, or even aware that they exist. It seems in this age of erosion and soil conservation that we should be more conscious of nature's safeguards against the former. In addition, liverworts make fine material for study, and are usually available within a short distance of any college or high school. The Iowa Wesleyan College Herbarium lacked liverworts. This preliminary study was started to add liverworts to the herbarium. Dr. Conard of Grinnell College, in his report on "Bryophyta of Iowa" (The Bryologist, Vol. 48, page 70), has record of only two …

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The Leaf Organization Of Adiantum Capillusveneris L. In Comparison With That Of Adiantum Pedatum L., Robert B. Wylie Jan 1948

The Leaf Organization Of Adiantum Capillusveneris L. In Comparison With That Of Adiantum Pedatum L., Robert B. Wylie

Proceedings of the Iowa Academy of Science

The genus Adiantum has few northern members but includes over a hundred tropical and subtropical species. Our chief northern representative, A. pedatum, ranges from Georgia to Nova Scotia, westward to the Pacific and north to Alaska. The other common temperate species, A. capillus-veneris, widespread in tropical and subtropical areas, is found chiefly in the southern part of the United States with limited northward extensions. While these two species overlap somewhat in their major distribution they belong to different geographical areas, but are similarly influenced by local conditions of substrate and habitat.

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Color Characteristics Of Certain Acid-Base Indicators, George W. Brown, Lothrop Smith Jan 1948

Color Characteristics Of Certain Acid-Base Indicators, George W. Brown, Lothrop Smith

Proceedings of the Iowa Academy of Science

It was found that students have difficulty in observing end points when titrating with methyl red and methyl orange as indicators, because of the comparatively large volume of solution necessary to cause a definite color change. Methyl orange-xylene cyanole was purchased from Eastman Kodak Company to overcome this difficulty. However, it was found that the color change of this mixed indicator was not completely satisfactory. A study has been made to obtain an indicator which presented the best possible color characteristics combined with the lowest pH interval for the titration of strong acids and bases. Four indicators were studied. They …

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The Antimonous-Antimonic Complex In Hydrochloric Acid, Frank Edwards, Adolf Voigt, Harvey Diehl Jan 1948

The Antimonous-Antimonic Complex In Hydrochloric Acid, Frank Edwards, Adolf Voigt, Harvey Diehl

Proceedings of the Iowa Academy of Science

A successful theory systematizing or correlating the color of inorganic complexes has not yet been advanced. Linus Pauling in his Richards Medal address (7) listed such a theory as one of the "puzzling unsolved problems of structural chemistry". The colors developed by solutions containing the same element in different valence states is particularly interesting, in that the color of the mixture may be radically different from that of either component. Cuprous chloride in concentrated hydrochloric acid is colorless, cupric chloride in a similar solution is green; present together they produce a dark brown or black solution (3). Similarly, a hydrochloric …

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Use Of A Zinc Spiral In The Titrimetric Determination Of Uranium, John H. Mcclure, Charles V. Banks Jan 1948

Use Of A Zinc Spiral In The Titrimetric Determination Of Uranium, John H. Mcclure, Charles V. Banks

Proceedings of the Iowa Academy of Science

A number of methods are reported in the literature for determining uranium titrimetrically by reducing hexavalent uranium to the tetravalent state and titrating the latter by means of standard oxidizing agents. Of these methods of reduction probably the most common is the use of a Jones reductor using amalgamated granular zinc as the packing material (3). Silver (1), lead (6) or cadmium (8, 9) packing for the reductor is also used. Other methods use aluminum (5, 2, 4) or copper (7) spirals. All these methods are reported as giving satisfactory results but certain difficulties are encountered in each of them. …

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Raman Tube Filters, Geo. Glockler, John F. Haskin Jan 1948

Raman Tube Filters, Geo. Glockler, John F. Haskin

Proceedings of the Iowa Academy of Science

A method for the application of plastic filter dopes to Raman tubes was developed. Such filters were devised for isolation of the 4358. A mercury triplet, which was used as the exciting source. Derivatives of nitrobenzene dissolved in a urea-melamine-formaldehyde resin effectively removed the 4047. A pair. During long ex-posures to mercury lamp radiations, these filters darkened. A film of light stable Eastman Acetate Lacquer 390-37-2 served the same purpose. Removal of continuous background was effected by Rhodamine 5GDN Extra in polymethyl methacrylate, Tygon lacquers, cellulose acetate, cellophane, or urea-melamine-formaldehyde resins. An Eastman gelatin filter produced similar results. A filter …

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An Extension Of A Volumetric Method For Aluminum To The Determination Of Milligram Quantities, Walter N. Trump, Lothrop Smith Jan 1948

An Extension Of A Volumetric Method For Aluminum To The Determination Of Milligram Quantities, Walter N. Trump, Lothrop Smith

Proceedings of the Iowa Academy of Science

Snyder (3) has given a rapid and precise titrimetric procedure for the determination of aluminum in the presence of moderate amounts of other substances. The original method was applied to samples containing from 0.025 to 0.13 gram of aluminum. In the present work it was found that, with certain modifications, the same procedure could also be used for the determination of alumim1m in the range of 5 to 25 milligrams. The precision of the modified method was found to correspond to a standard deviation of about 0.1 milligram throughout this range.

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A Measure Of Retroactive Inhibition In Motor Learning, A. H. Shephard Jan 1948

A Measure Of Retroactive Inhibition In Motor Learning, A. H. Shephard

Proceedings of the Iowa Academy of Science

In everyday life it is a common experience to find that some established response interferes with the learning of some new response. Thus the automobile driver finds it somewhat difficult to learn to shift gears using a control on the steering column after having shifted them by means of an older type control. The typist finds that she has trouble learning to type on a second keyboard in which the keys are located in relatively different positions. These are examples of a phenomenon known as proactive inhibition. This term is generally used to refer to a decrement in performance or …

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An Investigation Of Learning In A T-Maze With Relevant Drives Satisfied, Irving Maltzman Jan 1948

An Investigation Of Learning In A T-Maze With Relevant Drives Satisfied, Irving Maltzman

Proceedings of the Iowa Academy of Science

Psychologists agree, in general, that the role of motivation in determining the behavior of organisms is an important one. However, different interpretations arise when one attempts to specify precisely what this role may be. Some psychologists believe that motivation serves only as a forcer or activator of behavior. Others hold that in addition to being an activator of behavior motivation must be reduced for learning to occur. Thus, field theorists such as Tolman and Leeper state that the acquisition of learning is not a function of the number of reinforcements, or drive state reductions. Rather, acquisition is dependent upon the …

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Previous Learning As A Factor Influencing Perception Of The Phi-Phenomenon, M. E. Wingett, C. F. Haner Jan 1948

Previous Learning As A Factor Influencing Perception Of The Phi-Phenomenon, M. E. Wingett, C. F. Haner

Proceedings of the Iowa Academy of Science

The first serious attempt at control and analysis of apparent movement was made by Exner in 1875. At first he believed it to be the result of 'diffusion circles' emanating from each of the retinal points stimulated, but when the phenomenon was elicited by stimulating a point in each retina he advanced as his explanation a tendency of the observer to see motion whenever the stimuli received made such an appearance possible. Stratton, in 1902 and 1911, reported on his investigations and gave an explanation in terms of a conscious organization of sensations. He spoke of a 'relational activity of …

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Abstract Of Measurements Of Gamma-Ray Energies With The Beta-Ray Spectrometer, E. N. Jensen, L. Jackson Laslet, William W. Pratt Jan 1948

Abstract Of Measurements Of Gamma-Ray Energies With The Beta-Ray Spectrometer, E. N. Jensen, L. Jackson Laslet, William W. Pratt

Proceedings of the Iowa Academy of Science

An iron-free magnetic lens beta-ray spectrometer has been constructed. The spectrometer is mounted with its axis parallel to the earth's magnetic field. The spectrometer chamber has been constructed of aluminum tubing in order to reduce electron scattering to a minimum. The spectrometer has been used for the determination of gamma-ray energies from Zn65 and Co60.

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The Occurrence Of Rhipicephalus Sanguineus And Liponyssus Bacoti In Iowa, Elery R. Becker Jan 1948

The Occurrence Of Rhipicephalus Sanguineus And Liponyssus Bacoti In Iowa, Elery R. Becker

Proceedings of the Iowa Academy of Science

A year ago the writer presented at these meetings a paper discussing the distribution of the tropical rat flea, Xenopsylla cheopis, in Iowa and other interior states. Now he will present evidence that two acarines generally associated with tropical fauna may have become more or less permanently established inside the state. They are Rhipicephalus sanguineus, the brown dog tick, and Liponyssus bacoti, the tropical mite.

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A List Of Iowa Ostracods With Descriptions Of Three New Species, William Danforth Jan 1948

A List Of Iowa Ostracods With Descriptions Of Three New Species, William Danforth

Proceedings of the Iowa Academy of Science

The Ostracoda, together with the Copepoda and Cladocera, make up what is probably the most plentiful group of metazoan fauna in ponds, lakes, and, to a lesser extent, in streams. In spite of their numerical importance, no survey of ostracod species has been made for Iowa, although Gerhardt (1940) recorded Cypridopsis vidua and Cyprinotus pellucidus as occurring in Iowa.

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An Epitomized Compilation Of A Bird Census Now In Progress In The Area Of Mt. Pleasant, Iowa, Archie Euwer Jan 1948

An Epitomized Compilation Of A Bird Census Now In Progress In The Area Of Mt. Pleasant, Iowa, Archie Euwer

Proceedings of the Iowa Academy of Science

The object of this problem is to obtain accurate data on the species of birds to be found in this region, and the number of each species. Each week as many hours as possible are spent in the field collecting information. Due to unavoidable circumstances the total number of hours afield varies considerably each week. This census is not intended to be a complete survey of the birds in this area, rather it is a preliminary study and its purpose is to serve as an incentive for future students of biology to pursue this problem so that eventually an accurate …

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Subspecies In Iowa Ornithology, James Hodges Jan 1948

Subspecies In Iowa Ornithology, James Hodges

Proceedings of the Iowa Academy of Science

A brief search of ornithological literature reveals that during the last two years (1946 and 194 7), 27 important papers have been published dealing either directly or indirectly with subspecies of North American birds. If we were to include Mexico, Arizona, and tropical areas in this count it would of course be much higher. On the other hand, from 1941-1945 only one paper was published in the pages of IOWA BIRD LIFE dealing exclusively with the question of subspecies. From 1941-1947 a few short notes appeared within the pages of this journal mentioning subspecies. It is the purpose of this …

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A List Of The Leafcutting Bees (Family Megachildae, Hymenoptera) Known To Occur In Iowa., H. E. Jaques Jan 1948

A List Of The Leafcutting Bees (Family Megachildae, Hymenoptera) Known To Occur In Iowa., H. E. Jaques

Proceedings of the Iowa Academy of Science

Almost everyone has noticed the round holes nearly a half inch across cut in the leaves of many plants. Rose leaves very frequently show this mutilation. The casual observer is usually without information, however, as to how it all comes about unless he has chanced to see a leafcutter bee providing herself with one of the round oval pieces of leaf she uses in lining a burrow in rotten wood or in hollow plant stems. One must watch quickly and closely if he is to see this performance. With her sharp mandibles this agile bee hastily scissors out the leaf …

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A Tropical Ant Temporarily Established In Iowa, Robert L. King Jan 1948

A Tropical Ant Temporarily Established In Iowa, Robert L. King

Proceedings of the Iowa Academy of Science

Cosmopolitan tramp species of ants have been widely disseminated by man. About a dozen species have been introduced and are found in dwellings, greenhouses, nurseries and in and around urban communities in the southern and eastern parts of the United States. One of these, the Argentine ant, Iridomyrmex humilis Mayr, has become a serious pest in the southern states from Florida to California. It has also spread throughout the tropics and has in many areas replaced both native species and other earlier introduced species. Only one introduced species, the cosmopolitan Pharoah's ant, Monomorium pharaonis (Linn), has been reported from Iowa …

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Leucochloridium Sporocysts From The Okoboji Region, Lois Mcintosh Jan 1948

Leucochloridium Sporocysts From The Okoboji Region, Lois Mcintosh

Proceedings of the Iowa Academy of Science

The "throbbing" brood-sacs of the fluke Leucochloridium which are sometimes found in the tenacles of snails belonging to the genus Succinea are indeed spectacular. Two examples of the sporocysts were found in a collection of eleven Succinea retusa taken on July 29, 1947, at the hanging bog on the west shore of Silver Lake, Dickinson County, Iowa. Only one sporocyst included a mature brood-sac, this was about 5.0 X 1.5 mm. with a long (20 mm.) thin stalk connecting it to the rest of the sporocyst. Its distal end was capped with red-brown; immediately below this a narrow creamwhite band …

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