Life Sciences Commons^™

Size And Structure Of Leaves Of Cereals In Relation To Climate, William Edward Bruner, John E. Weaver

Papers from the University Studies series (University of Nebraska)

Although a very large amount of work has been done on the variation in form, size, and anatomical structure of native plants grown under different conditions, relatively little attention has been given to similar studies of crop plants. As far as we are able to ascertain, no investigations have been made of variation in the leaves of cereal crops grown under widely different, measured environments.

During the past few years (1920-23), in connection with studies on the development and activities of the roots of crop plants (Weaver, Jean, and Crist, 1922), plant production as a measure of environment (Weaver, 1924), …

Further Studies In The Ecotone Between Prairie And Woodland, R. J. Pool, J. E. Weaver, F. C. Jean

Papers from the University Studies series (University of Nebraska)

A series of intensive investigations of the ecological features of the tension zone between prairie and woodland in the Mississippi valley was begun by Weaver and Thiel in 1915. These studies were continued for two seasons in Minnesota and were also extended to the prairies of eastern Nebraska in 1916. These investigations represent the first attempt to attack the prairie-forest problem on a comprehensive scale by means of the quantitative methods of modern ecology. Some of the results secured from these studies have been published as the first paper of a series planned to deal with critical investigations in the …

Histological Studies In The Artemisia Formation, Raymond John Pool

Papers from the University Studies series (University of Nebraska)

Many investigators have written on the subject of leaf histology and morphology in general, and a few have, in addition, touched upon the physiological significance of structures found during the progress of the study. Among these writers are Haberlandt, Pick, Stahl, Bonnier, Wagner, Hesselmann, and Clements. Most of the work, however, has been purely histological or morphological with little or no reference to environic forces. But in these later days of the development of the new ecology those forces or factors which have been potent in the evolution of plants and which are moulding plants today have come under careful …

On The Structure Of The Pistils Of Some Grasses, Elda Rema Walker

Papers from the University Studies series (University of Nebraska)

The purpose of this investigation has been to determine to what extent there is evidence of a third carpel in the pistils of grasses. The study has been carried on, by means of cross and longitudinal sections, cut in different planes, as well as by a study of the external appearance of the pistils. The following are the results obtained:

Tribe Festuceae

Tribe Hordeae

Tribe Chlorideae

Tribe Aveneae

Tribe Agrostidcae

Tribe Phalarideae

Tribe Oryzeae

Tribe Paniceae

Tribe Andropogoneae

Tribe Maydeae

EXPLANATlON OF PLATES

On The Movements Of Petals, Esther Pearl Hensel

Papers from the University Studies series (University of Nebraska)

The following paper has to do with an investigation of the physical causes· which bring about opening and closing movements, periodic or otherwise, of certain flowers. With that end in view, seven different species of flowering plants have been experimented upon directly, a much larger number being simply observed with respect to the nature, time, etc., of their anthotropic movements. Movement consists in the corolla taking upon itself either the open or closed position for certain periods of the day or night; for example, the morning glory (Ipomoea purpurea) opens early in the morning (from 4:00 to 5 …