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Some Notes On Empoasca Flavescens Fabricius (Homoptera, Cicadellidae), R. L. Webster Jan 1922

Some Notes On Empoasca Flavescens Fabricius (Homoptera, Cicadellidae), R. L. Webster

Proceedings of the Iowa Academy of Science

In the fall of 1910 my attention was called to the abundance of this leaf-hopper on certain trees of Ptelea trifoliata on the Iowa State College campus at Ames. Some notes on the insect were made that fall and also in the two years following. Practically nothing has been known concerning the life history of this insect; hence this paper. The notes are from the files of the entomological section of the Iowa Agricultural Experiment Station.

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Notes On The Flora Of Yosemite And Adjacent Regions, L. H. Pammel Jan 1922

Notes On The Flora Of Yosemite And Adjacent Regions, L. H. Pammel

Proceedings of the Iowa Academy of Science

I shall not try to make an extensive paper on the flora of the Yosemite, but merely to record my impression of this interesting floristic region.

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The Relation Of Cucurbit Mosaic To Wild Catnip, J. H. Muncie Jan 1922

The Relation Of Cucurbit Mosaic To Wild Catnip, J. H. Muncie

Proceedings of the Iowa Academy of Science

Cross inoculations from mosaic cucurbits to non-cucurbitaceous hosts, according to published records, have been unsuccessful except in a few cases. Doolittle obtained infection by aphis inoculation from mosaic cucumbers to Martynia louisiana, while Jagger obtained infection on Lobelia crinus var. Gracilis and Helianthus debilis. Preliminary experiments by the writer show that cucurbit mosaic can be transmitted to Nepeta cataria by the insertion of crushed mosaic leaf tissue of mosaic gourd into the stems of Catnip. Typical mosaic symptoms appeared on the tips of the leaves of the catnip in about three weeks, and after six …

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A Chemical Classification Of The Activities Of Soil Microorganisms, Paul Emerson Jan 1922

A Chemical Classification Of The Activities Of Soil Microorganisms, Paul Emerson

Proceedings of the Iowa Academy of Science

At the present time it may be said that the process of decomposition with its resultant complex chemical changes taking place in the soil is controlled primarily by the activities of micro-organisms and that Soil Fertility is mainly dependent upon these microscopic forms.

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Coefficients Of Diffusion Of Salt Vapors In The Bunsen Flame, George E. Davis Jan 1922

Coefficients Of Diffusion Of Salt Vapors In The Bunsen Flame, George E. Davis

Proceedings of the Iowa Academy of Science

The coefficients of diffusion of alkali salts in the Bunsen flame have been determined by a photographic method which is a modification of the method used by H. A. Wilson. The values of the diffusion coefficients obtained for sodium, potassium, and caesium salts are roughly proportional to the reciprocals of the atomic weights of the metals. This is what we should expect from kinetic theory, if we consider the luminosity to be due to free metal atoms in the flame. Lithium salts, however, are found to have a lower coefficient of diffusion than sodium salts, and hence their metal atoms …

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Officers, Past Presidents, And Members, Iowa Academy Of Science Jan 1922

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

Proceedings of the Iowa Academy of Science

No abstract provided.

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Table Of Contents Jan 1922

Table Of Contents

Proceedings of the Iowa Academy of Science

No abstract provided.

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The Address Of The President - The Cosmology Of The Universe, D. W. Morehouse Jan 1922

The Address Of The President - The Cosmology Of The Universe, D. W. Morehouse

Proceedings of the Iowa Academy of Science

Astronomy is the original science. Its scope comprehends all the physical sciences - geology, physics, chemistry - and even the natural sciences. All borrow from it, and in turn contribute to astronomical knowledge. Moreover, from the very beginning, the study of astronomy has been inseparably connected with philosophy and religious speculation. For its theme - its age-long objective - has been a true world concept. I quote: "Back of every religion, and of every philosophy or science, worthy of the name, lies a world-view, a concept in which are included all localities and all beings supposed in that religion or …

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Decorative Markings On Some Fragments Of Indian Pottery From Mills County, Iowa, Paul R. Rowe Jan 1922

Decorative Markings On Some Fragments Of Indian Pottery From Mills County, Iowa, Paul R. Rowe

Proceedings of the Iowa Academy of Science

Among the articles of Indian workmanship in the writer's possession are several hundred fragments of soft dark pottery. All may be well described as dark gray, porous and more or less sandy. Only one specimen is distinctly red. The thickness of the different pieces varies from one-eighth to one-half an inch. To judge by the curvature of the pieces the whole pots must have ranged from a quart to four or five gallons in capacity. Almost all of these potsherds were picked out of the wash along the beds of Pony creek and some smaller runs near Glenwood, Iowa. A …

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Till-Like Deposits South Of Kansas River In Douglas County, Kansas, Walter H. Schoewe Jan 1922

Till-Like Deposits South Of Kansas River In Douglas County, Kansas, Walter H. Schoewe

Proceedings of the Iowa Academy of Science

The line marking the position of the maximum advance of the Kansan ice sheet in northeastern Kansas has been established by investigators at various places as lying either north or south of Kansas or Kaw River. The earlier maps show the drift border as being south of the river and extending at least as far south as 38° 50' north latitude. Of the more recent work that done by Todd not only represents the latest but also the most thorough. This investigator locates the edge of the Kansan ice sheet as lying north of the Kaw River valley from a …

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Some New Paleozoic Glass-Sponges From Iowa, A. O. Thomas Jan 1922

Some New Paleozoic Glass-Sponges From Iowa, A. O. Thomas

Proceedings of the Iowa Academy of Science

Fossil sponges of any kind are relatively rare in the Paleozoic rocks of Iowa and especially so if we except the questionable forms generally relegated to the Receptaculitidae.

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Some Black River Brachiopods From The Mississippi Valley, Carroll Lane Fenton, Mildred Adams Fenton Jan 1922

Some Black River Brachiopods From The Mississippi Valley, Carroll Lane Fenton, Mildred Adams Fenton

Proceedings of the Iowa Academy of Science

This study originated in the attempt to identify a number of Rhynchotremas and Zygospiras from the Plattin and Decorah formations of Ste. Genevieve County, Mo. Comparisons were made with sets from several other localities in the Mississippi valley, and thus considerable additional material was examined, involving not only Black River horizons, but the Kimmswick and Maquoketa as well.

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Laramian Hiatus Around The Southern Rockies, Charles Keyes Jan 1922

Laramian Hiatus Around The Southern Rockies, Charles Keyes

Proceedings of the Iowa Academy of Science

For a long time after the vast coal fields which extend around the southern extremity of the Rocky Mountains in southern Colorado and northern New Mexico, came under close surveillance of stratigrapher their deposition was regarded as having taken place during the closing epoch of the Cretacic Period. The great thickness of the associated strata were paralleled with the enormously thick Laramie coal-bearing beds of Wyoming and Montana. On this point a voluminous literature appeared to be in general agreement.

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Pyrite In Coal, J. M. Lindly Jan 1922

Pyrite In Coal, J. M. Lindly

Proceedings of the Iowa Academy of Science

A general discussion of this subject is not intended in this article, only the consideration of a deposit of pyrite in coal of a very unusual nature.

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Deductions From The Occurrence And Character Of Two Large Quartzose Conglomerate Boulders Of Unknown Origin Found In The Kansan Drift Sheet At Centerville, Iowa, Ben H. Wilson Jan 1922

Deductions From The Occurrence And Character Of Two Large Quartzose Conglomerate Boulders Of Unknown Origin Found In The Kansan Drift Sheet At Centerville, Iowa, Ben H. Wilson

Proceedings of the Iowa Academy of Science

On a lawn at No. 629 West Maple Avenue, in Centerville, Iowa, are located two large quartzose conglomerate boulders which are of more than usual interest. These were removed from the glacial till during the process of excavating for the cellar under the dwelling now situated on the same lot and when found were said to be buried beneath several feet of drift material.

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The Status Of Sedimentation In Iowa, A. C. Trowbridge Jan 1922

The Status Of Sedimentation In Iowa, A. C. Trowbridge

Proceedings of the Iowa Academy of Science

Iowa need not be ashamed of the part her geologists have played, either in the past history of sedimentation, or in the recently renewed American activity on this important, but too long neglected subject. There being no igneous rocks in situ within the state and practically no exposures of metamorphic rocks, all the work which has been done on the geology of the state during the years is more or less closely related with sedimentation. The more recent investigations of breccias by Professor W. H. Norton, of gumbotils by Dr. George F. Kay, of Pennsylvanian stratigraphy and structure by Dr. …

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Schedules For The Field Descriptions Of Sedimentary Rocks, A. C. Trowbridge Jan 1922

Schedules For The Field Descriptions Of Sedimentary Rocks, A. C. Trowbridge

Proceedings of the Iowa Academy of Science

An explanation of the schedules recently reported by a subcommittee of the committee on sedimentation of the National Research Council, and presentation to each of those present of mimeographed copies of the introduction to these schedules, and of printed copies of the schedules themselves. These materials were furnished the writer by Dr. M. I. Goldman, Chairman of the committee.

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Origin Of Limestone Conglomerates, Louise Fillman Jan 1922

Origin Of Limestone Conglomerates, Louise Fillman

Proceedings of the Iowa Academy of Science

A study of the literature reveals at least eight ways in which limestone conglomerates may be formed. The following ways are noted and described in the paper: (1) derivatives from some pre-existing rock; (2) by deformation of the laminae; (3) by pebbles derived from concretions; (4) by the secretions of limestone nodules by algae; (5) by the breaking of thin layers of limestone by storm waves; (6) by subaquatic gliding of limestone layers ; (7) by lime-mud being cracked on a tidal beach; (8) by minor oscillations of the sea and the erosion of materials previously deposited.

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Notes On Some Mammalian Remains Reported In Iowa During The Past Year, A. O. Thomas Jan 1922

Notes On Some Mammalian Remains Reported In Iowa During The Past Year, A. O. Thomas

Proceedings of the Iowa Academy of Science

Road-making activity, the opening of new gravel pits and drainage ditches, and natural erosion have brought to light an unusually large number of fossil bones. A large ditch near Avoca has yielded an excellent skull of the giant beaver, Castoroides ohioensis, and at the same place a humerus of the great ground sloth Megalonyx. From Wayland comes a perfect tibia of the same kind of sloth and near it was found the crown of an unerupted mastodon molar. A well preserved, but worn down, tooth of the Columbian elephant was found in a gravel pit at Hartley and …

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A Comparison Of Intensities Required Under Direct And Under Indirect Lighting Systems, Wm. Kunerth Jan 1922

A Comparison Of Intensities Required Under Direct And Under Indirect Lighting Systems, Wm. Kunerth

Proceedings of the Iowa Academy of Science

Although artificial indirect lighting dates back twenty-five years or more, it was not very extensively patronized until after 1906 when the advent of the more efficient Mazda B lamp made its commercial use possible. At once comparisons were made between the direct and the indirect systems on various points.

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Phenomena In Gases Excited By Radio Frequency Currents, E. O. Hulburt Jan 1922

Phenomena In Gases Excited By Radio Frequency Currents, E. O. Hulburt

Proceedings of the Iowa Academy of Science

The spectra from hydrogen, oxygen and air excited by currents of the frequency of the order of 106 alternations per second produced by an oscillating fifty-watt electron tube were photographed with a grating spectrograph in the spectral region from 5000 A to 3500 A. These spectra were found to be identical with the spectra of the same gas stimulated by sixty-cycle current of the same strength as the radio frequency current.

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Nodal Distances In Acoustics, G. W. Stewart Jan 1922

Nodal Distances In Acoustics, G. W. Stewart

Proceedings of the Iowa Academy of Science

Our elementary texts discuss the nodal planes produced by two plane waves of the same amplitude and frequency travelling in opposite directions and leave us with the impression that the distance between nodal surfaces is usually one-half of the wave length. Yet this is far from the truth. Nodal surfaces having such a distance apart exist only for plane waves, the most common case being the standing waves in pipes. The purpose of this note is to call attention to a case wherein the distance from a nodal to a loop surface can be made very short, almost as short …

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The Scattering Of Homogeneous X-Rays Of Wave Length .712 A° Unit By Carbon, Lithium, And Hydrogen, C. W. Hewlett Jan 1922

The Scattering Of Homogeneous X-Rays Of Wave Length .712 A° Unit By Carbon, Lithium, And Hydrogen, C. W. Hewlett

Proceedings of the Iowa Academy of Science

The angular distribution of the scattering of the Ka radiation from a molybdenum X-ray tube by powdered graphite, diamond splints, benzene, mesitylene, and metallic lithium has been determined with an X-ray spectrometer by the ionization method. The solid substances give maxima of scattering in the places found by the photographic method, but the relative intensities of the scattering at different angles measured by the ionization method is greatly different from that estimated from the photographic method.

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The Broadening Of The Balmer Lines Of Hydrogen With Pressure, E. O. Hulburt Jan 1922

The Broadening Of The Balmer Lines Of Hydrogen With Pressure, E. O. Hulburt

Proceedings of the Iowa Academy of Science

Spectrograms were taken of Hß, HY and Hδ of hydrogen excited by condensed discharges for gas pressures from 2 to 135 mm. of mercury. At the highest pressure the photographic widths of the lines were nearly 100 A.U. Throughout the series of pressures the intensity of the central portions of Hß was maintained sensibly constant. Assuming that the widening was caused by disturbance of the uniformity of the radiation due to collisions of the radiating particles (as proposed by others), the widening of the lines with pressure was calculated and found to be considerably less than that observed. This …

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Hall Effect And Specific Resistance In Evaporated Films Of Silver, Copper And Iron, J. C. Steinberg Jan 1922

Hall Effect And Specific Resistance In Evaporated Films Of Silver, Copper And Iron, J. C. Steinberg

Proceedings of the Iowa Academy of Science

Previous investigators have found the specific resistance a constant for metallic films, until the thickness becomes comparable with particle dimensions, at which thickness the resistance becomes very great. Wait found the resistivity of chemically deposited silver films, whose thicknesses were greater than the above mentioned critical thickness, to be only slightly greater than that of the bulk metal. He found the Hall Effect in these films, as well as in films whose thicknesses were less than the critical thickness, to be the same as that of bulk silver. On the conception that the substance in a film consists of granules …

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Iowa Microlepidoptera, A. W. Lindsey Jan 1922

Iowa Microlepidoptera, A. W. Lindsey

Proceedings of the Iowa Academy of Science

After writing my last paper on the Lepidoptera of Iowa, viz., "Some Iowa Records of Lepidoptera," I still had in my possession a considerable number of specimens of Tineoidea and all of the Phycitinae which I had taken in the state. I attempted to work up this material during my last few months as curator of the Barnes collection at Decatur, Illinois, and succeeded with most of the Tineoidea. The subfamily Phycitinae of the Pyralidae is in such great need of careful revision that I feel safer in omitting it entirely at present, though I have identified a few species …

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Brood A Of The May Beetles Extends Its Range In Iowa, H. E. Jaques Jan 1922

Brood A Of The May Beetles Extends Its Range In Iowa, H. E. Jaques

Proceedings of the Iowa Academy of Science

Among the well-known insect pests with which the farmer must contend are the May beetles which in the larva stage, as white grubs, do heavy damage to the grasses, corn, potatoes, strawberries and garden crops. There are about one hundred species of May beetles known to occur in the United States all of which belong to the genus Phyllophaga. Forbes in examining 114,493 May beetles in Illinois found 34 species, but less than half of these were sufficiently abundant to be of serious economic importance.

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A Study Of The White Marked Tussock Moth, Susannah Poulter Jan 1922

A Study Of The White Marked Tussock Moth, Susannah Poulter

Proceedings of the Iowa Academy of Science

Early in the winter of 1921-22 it was observed that egg masses of the white marked tussock moth, Hemerocampa leucostigma Smith and Abbot were unusually abundant. Taking advantage of this opportunity it was planned to make a careful study of the life history of that interesting insect. This insect is of considerable economic importance in that the larvae when abundant defoliate trees of various species.

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Observations On The Cranial Nerves Of Certain Ganoids, H. W. Norris Jan 1922

Observations On The Cranial Nerves Of Certain Ganoids, H. W. Norris

Proceedings of the Iowa Academy of Science

The forms considered are Amia and Lepidosteus (Holostei), and Polyodon and Scaphirhynchus (Chondrostei). The cranial nerves of these forms bear very obvious relations to the degree of development of certain external sense organs. That Amia and Lepidosteus are teleost-like in their nerve relations accords with the common view of their relationships in general; Polyodon and Scaphirhynchus on the other hand show in their cranial nerves elasmobranch relations.

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Simultaneous Fast And Slow Drum Records Of Fatigue, Francis Marsh Baldwin Jan 1922

Simultaneous Fast And Slow Drum Records Of Fatigue, Francis Marsh Baldwin

Proceedings of the Iowa Academy of Science

The essential details of fatigue processes as they develop in a properly prepared protoplasmic system like that of a frog muscle, are conveniently transcribed by the writing lever either upon a kymograph drum revolving comparatively rapidly, or one going very slowly and these records furnish data for subsequent analysis. In each procedure some facts' are obtained as to amplitude, enhancing and diminution of responses under a given rate of stimulation and under certain physical and physiological conditions, but unfortunately neither method alone suffices for the proper analysis of the whole process. Although details of mechanical devices differ somewhat in the …

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