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Field collections and observations of Alaria (Order Laminariales) were made throughout the intertidal zones of the temperate areas in the Northern Hemisphere. In addition a study was made of all available herbarium material. Morphology was chosen as the basis of the systematic study of the genus. The systematics of the genus were studied by a discriminant and distance function analysis, using an IBM 1620 computer. From this analysis, the characteristics of 10 species were defined. Four other species were described from herbarium material, but were not sampled in sufficient quantity for statistical analysis. The dividing lines drawn between the various species are meaningful but essentially arbitrary. Confusion in the taxonomy of the genus has two main sources. First, the taxa are not completely differentiated into distinct species. Second, differences of environment appear to play a greater role as a cause of morphological variation than do differences of genotype. The names of 107 specific and subspecific taxa of the genus Alaria, including recombinations, were discovered in an exhaustive search of the literature. Of these 107 names, 19 were eliminated as illegitimate under the rules of the International Code of Botanical Nomenclature, or were removed from the genus. The genus Pleuropterum Miyabe et Nagai was reduced to synonomy under the genus Alaria. The conservation of the generic name Alaria was re-examined and found to be adequate. A thorough search was made for possible holotypes or lectotypes of the 88 taxa remaining. Material was either shown to be the holotype or found and designated as the lectotype for 66 taxa. No relevant material could be found for 11 more of these taxa and possible material for another 11 was judged inadequate for practical systematic purposes. / Science, Faculty of / Botany, Department of / Graduate

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Typescript (photocopy). / Digitized by Kansas Correctional Industries

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A series of experiments was completed in which the morphology, anatomy and biochemistry of two Melilotus species, Melilotus alba and Melilotus officinalis, were studied. The purposes of the study were to illustrate whether the variability of specimens was due to polymorphism or speciation and to isolate the factors that have separated these specimens as competitors.The effects of impaction and scarification on the germination of M. alba and M. officinalis seeds were studied, as were the effects of light and temperature stimuli on germination and growth The rate of plant maturation and the chronology of flowering for the two species were investigated. Maturation differences were minor, but the chronologies of flowering deviated markedly.The techniques of one- and two-directional thin layer chromatography were used to separate the free amino acids in Melilotus seed extract preparations. The technique of polyacrylamide gel electrophoresis was used to separate the proteins in these preparations. In every experiment, the two Melilotus "species" were genus specific with no species variables in terms of the amino acid and protein complements.

The objectives of this study were to describe the variability, to evaluate the combining ability, and to calculate the heritability values for certain characteristics of Coastal Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco var. menziesii. Four trees (A, B, E, and 11) were selected on the University of British Columbia Campus. Three of them were selected from the local natural population while the fourth came from an unknown provenance. The investigation of variation included phonological observations on flushing and flowering times, and quantitative descriptions of pollen, seed and cone size. A survey of Campus trees showed that Douglas-fir is extremely variable in the time of flushing and flowering, the size of pollen, seed and cones, and the total number of filled seeds. Times of flushing did not determine times of flowering. There was a strong negative correlation between pollen size and time of flowering. This suggests existence of adaptive significance to adverse climatic condition. Variation in width of the cone was greater than in cone length. Seed germination percentage appeared to be inherited on a single factor basis, and the results from Fl crosses substantiated the suggestion that tree E might possess a homozygous dominant state. Filled seeds have not been obtained from tree B when it was self-pollinated. This supports Orr-Ewing's theory, that self-sterility might be an inbreeding effect caused by the action of lethal genes, when brought together in a homozygous state. Combining ability of the four study trees was tested by a polyallel cross with all sixteen possible combinations. The cross was completed in 1962, using three different pollination methods; dry, wet and dry-wet. Mortality of conelets was lowest in the case of wet pollination. Losses were doubled with dry pollination. Of 302 seed conelets pollinated, 201 were collected and 8,004 seeds were extracted from them. The number of filled seeds per cone was lowest in the cases of self-pollination (1.91) and wind pollination (3.05). Cross pollination on the average surpassed wind pollination by 4.6 times, and the self-pollination by 7.3 times, producing 13.81 filled seeds per cone. In order to minimize and test the variability due to environmental effects, the seedlings were grown under controlled environmental conditions. Two Percival (PGC-78) units were employed, one of them simulated long-day (15 hours illumination) and the other short-day (10 hours illumination) effects for 132 days. Tree 11, which was different in origin from the local provenance trees, showed the best combining ability as a seed parent. Progeny from crosses between trees from the same populations showed smaller values compared to progenies from crosses between trees from different populations. Epicotyls, for example, were 73-78 per cent longer on seedlings from tree 11 compared to seedlings from trees B and E, when pollen from tree A was applied. Obviously, further investigation of intra-specific crosses has practical merit. Heritability values in the narrow sense were calculated for twelve different juvenile seedling characteristics, and the practical application in relation to forest tree improvement was briefly discussed. / Forestry, Faculty of / Graduate

The papers in this thesis represent a series of attempts — empirical and theoretical — to integrate developmental biology with population level studies of variation; to initiate a "developmental population biology" which would complement the well established fields of population ecology and population genetics. The introductory chapter traces the development of the conceptual ideas from the context of the maturation of a single research group. There follow three empirical chapters based on population studies of yellow cedar (Chamaecyparis nootkatensis). The first of these chapters examines the interdependency of progeny growth variation on parentage and stand structure and argues that parentage, developmental history and environmental contingencies can interact in complex ways to structure the variation observed in natural stands. The second chapter examines time related changes in patterns of variation for mainstem growth and needle initiation data of seedlings, and finds that the majority of the increase in variation with time results from differentiation among individual seedlings. The third chapter examines the nature of intra-individual variation in needle (from seedlings) and scale (from mature trees) data from the perspective of the concept of morphological integration, the amount and structure of covariation within an individual. The results of this chapter demonstrate that the nature of morphological integration changes during the course of development, and that variation in morphological integration — that is the pattern of variable relationships or covariance structure — distinguishes individuals. The final chapter is more theoretically oriented, and demonstrates how the patterns of increasing variation with time, and changing covariation with development (Chapters 2, 3) may be unified and explained in the context of developmental trajectories, where such trajectories represent the development of the form of individual organs through time in terms of point trajectories through a multivariate space. The nature of such developmental trajectories is ultimately a manifestation of cell division and elongation in various planes, resulting in the external form of the organs. Three increasingly complex graphical models of developmental trajectories are presented and it is argued that when developmental trajectories diverge from each other in a nonlinear manner, changes can occur in both correlation and covariance structures, coincident with changes in size. The relation between developmental trajectories and the production of variation within populations is further elaborated from the context of dynamical systems theory. / Science, Faculty of / Botany, Department of / Graduate