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The article discusses the impact which dual distribution and vertical integration in marketing organizations has in regards to marketing organizations. The part in which large manufacturing firms and small distribution firms play in regards to manufacturing and distribution in the U.S. is discussed. The relationship which manufacturing and distribution companies have with each other and the way in which this relationship has changed is discussed. According to the article, one of the changes which has occurred regarding distribution is the existence of dual distribution, in which a company distributes its products from more than one marketing organization.

Examines the biogeographical aspects of the marsupial-placental dichotomy in mammalian evolution in the Cretaceous period. Use of fossils in the study; Origin of marsupials; Development of other therian adaptations.

Examines the vertebrate distribution in continental drift. Concept of historical biogeography; Reconstruction of the phylogeny of organisms; Acceptance of plate tectonics by biologists.

Examines the equilibrium theory of island biogeography and ecology. Importance of islands to biologists; Concept of biotic depauperization; Use of the theory in the preservation of biotic diversity.

Examines the uses of cladistics in ecology. Contribution of cladists to biogeography; Definition of cladistic classification; Concept of phylogeny.

The article presents a review of literature on formal approaches to the analysis of the population genetics of small anthropological populations. It discusses a wide range of topics including genetic distances, genotypic disequilibrium, regional variation in gene frequencies, migration matrices, anthropometrics, population genetics and regional history. This literature concludes that the studies of the genetic structure of small populations have made particular and incidental contributions to formal genetics, to regional history and prehistory, to epidemiology and to several other fields to which they are peripheral, however, they have not advanced an understanding of human evolution in a global sense.

The article examines the evidence on hominid phylogeny primarily from amino acid sequences. It will also consider how well this sequence evidence is supported by immunological and deoxyribonucleic acids (DNA) data. These evidences include the relevant biochemical data that are taken from proteins and DNA, which are macromolecules that are extremely dense in genetic information and thus uniquely suited for mapping the genealogical relationships of species. Furthermore, this literature also reviews the efforts of many biochemical laboratories in discovering the sequences of various proteins in a range of primates and other species.

Focuses on a physiognomic classificationa of vegetation. Distribution of organinisms on earth; Use of maps as basic tools; Natural classification of vegetation.

Focuses on herpetogeny in Mexico and Guatemala. Phylogenies of groups; Fossil remains in adjacent areas; Modern physiography and herpesianlife areas.

Focuses on the distribution and affinities of Mexican mammals. Geographic ranges of genera; Natural units of the area.

The article discusses the problems of hydrology and plant distribution in mires. early concepts of the causes of differences in mire vegetation are inadequate in situations where the ground water is mobile. Many mires are said to be traversed by water tracks, whose characteristic vegetation appears to differs from that of the mire expanse because of the greater rate of horizontal movement of water through the peat of the tracks. the physical basis of such movement may be correlated with differences in the amplitude of oscillations in water table height. Present evidence suggests that aeration effects are probably secondary.

The article introduces some new classes of tests of randomness in plant distributions. The new tests involve only measurements from random sample points to plants. Their distributions are independent of the density of plants on the null hypothesis and on a wide class of alternatives. The tests are responsive to departures from randomness in an easily interpretable way. The ratio test is based on the sample mean of the ratio. While the correlation test is based on the sample correlation coefficient.

The article focuses on the spergula arvensis, a biological flora of the British Isles. It describes the spergual arvensis which has an annual herb with ascending geniculate stems, with 10 or fewer stamens, and the species is very variable. It is stated that the species is native and a locally abundant calcifuge weed of arable land, particularly on light sandy soils and offers information which includes the geographical and altitudinal distribution, habitat, its history of the species. It also presents several tables that show the variation in number of stamens per flower, relation between soil texture and occurrence of the species and number of fields in which the listed species were in abundant in association with spergula arvensis.

The article presents a study about the distributional pattern of Primula scotica in relation to its ecological amplitude. It examines the environmental changes in the past that have affected the reduction in the size of the area occupied by the plant. The study also analyzed the significance of seed dispersal and the availability of suitable habitats in order to determine the distribution. The natural barriers to the extension of the size of area occupied by P. scotica, including the prevalence of moorland and peat-bog vegetation and the insularity of localities, are discussed.

The article discusses the correlation between macro-distribution and micro-distribution of plant communities using the formulated "Geo-ecological Law of Distribution." Accordingly, the specific topographical distribution or micro-distribution of an ecotypic plant species or of a plant community is a parallel function of its general geographical distribution or macro-distribution. Furthermore, this two factors received special consideration including in genetic and historic factors. In addition, figures are also presented which shows the rapid changes in vegetation within three phytogeographical regions in a short distance.

The article focuses on the origin and geographical relationships which exist between the flora of the British Isles and that of the Continent. The distribution of plants over the earth's surface lies at the very foundation of all ecological investigations, since the structure and development of plant communities depend on the interaction of various factors. The article attempts to examine the close connection between detailed studies of the distribution of different plant species and the ecological problems affecting their geographical range. The admixture of geographical types composing the British flora has long been recognized, though not fully analyzed. It was found out that climate plays a significant role in the distribution of these species.

The article talks about an investigation which examines the impact of river on plant distribution. It reports that the vegetation in river valleys of the eastern part of the Eurasian continent displays a great and constant difference between the inundated and noninundated parts of the valley. It suggests that in different latitudes and climates plants change their habitats, and this change compensates for the lack of physiological adaptability, which is not so great as is generally supposed. It notes that in the same locality species and communities of more northern and more southern type exist side by side, ranging from desert vegetation to that of the northern swamps or tundra, each with its characteristic species, microclimate, soil conditions and even landscape.

The article presents a study on the factors affecting animal distribution in small streams at the Panama rainforest during the dry season. This paper focuses on the dry season in 1924 where water pooled along the lower yards of the Shannon Creek at the Northern side of Barro Colorado Island in Gatun Lake. Animals were collected and identified. They were recorded for their individual characteristics. Quantitative estimation were employed to study deeper the inhabitants of the river. Significant facts were collected and compared. The result of the experiment is discussed in brief.

The article provides information on the phytogeography and flora of the Mountain Summit Plateaux in Tasmania. It states that the vegetation of the area is very homogenous in character, relatively poor in species. It cites that the flowering season on the region's different mountains varies according to its latitude and season, of which the predominant flower colors are yellow to white and pink to red. In the Tasmanian mountains, herbaceous plants are more conspicuous by its absence than its presence under prevailing Austral-montane and sub-Antarctic conditions. It highlights the chief plant associations that are taken serially from the highest points downwards.

The studies were carried out in southern Sweden and dealt with factors affecting index line catches and the ratio between index line catches and population density. There is a pronounced repellant effect from trapped sexually inactive animals in multiple catching traps when the catch approaches 1 animal per trap. During these conditions animals which become active soon after the traps are set will be over-represented. The catch is also influenced by the type of trap and bait used. In order to obtain unbiased samples there should be many single catching traps per trapping point. It was possible to transfer line values to population density by combined index line/removal captures. The relations between index line catch and population density were very different in the species Apodemus flavicollis, A. sylvaticus and Clethrionomys glareolus, the catch of the first one being proportionally greatest. There was no significant evidence of different trappability of the species during the year. [ABSTRACT FROM AUTHOR]

The article discusses the relict concept. The words "relicta", "relictata", and "relictus" were used earlier as specific names. Chrysomela relicta was described already in 1801 by biologist J.C. Fabricius. As is usual during the period, though, Fabricius did not give any indication as to the reason for the name. It does not seem to be based on geographical circumstances. The descriptions of the species in question were frequently based on single specimens, and it looks more as though they were the scraps of the collection at hand. At the very beginning of the nineteenth century the conception of geographical relics or survivors had hardly emerged as yet. Discussions were certainly going on as to obvious differences in geographical distribution, but it was suggested that they were due to various centres of creation. A more modern view of zoogeography did not emerge until about the middle of the century. In all probability the names coined during the early nineteenth century did not influence the later use of the concept in biology.

The article focuses on the occurrence of Melampyrum Arvense in Sweden. While the species holds its position in Gotland and Oland, it has decreased enormously on the mainland. The appearance of this plant in most cases is limited to sandy or gravelly slopes, headlands, roadsides, often among shrubs. The species is also found growing in sand-mixed calcareous loam in Gotland. In spite of Gotland being one of the driest districts in Scandinavia, the soil keeps the humidity better than the sand and therefore gives the plant better conditions, with sufficient access of humidity, to survive in sunbaked surrounding. This plant can develop into luxuriant plants on certain perennials. When Gotland was originally populated it is possible that farmers coming from the mainland may have carried with them freshly ripened cereals containing seeds of M. arvense. Reports of Swedish botanical authors from old times plainly testify that Melampyrum arvense was formerly often observed on arable land and at that time, and also later on, the occurrence of the species on nearby headlands, shrub-thicket-margins, meadow-slopes or among piles of stones was regarded as secondary phenomena.

The seasonal and depth distribution of phytoplankton in Gull Lake, a moderately large, temperate, dimictic, recreational lake in southern Michigan, U.S.A., is described and discussed. Diatoms (Fragilaria crotonensis, Cyclotella michiganiana, Asterionella formosa, and Synedra acus) dominate the spring phytoplankton. Populations of cryptomonads, green flagellates, and non-bloom-forming blue-green algae (Chroococcus and Synechococcus) grow mainly in summer. Diatoms grew under the winter ice, and objections are lodged to the classic explanation of seasonal growth in temperate lakes, and to a recent hypothesis concerning the ‘paradox of the plankton’. Two raphe-bearing large diatom species were considered to be truly planktonic. A Synechococcus species was similar to that described previously only from Loch Leven. [ABSTRACT FROM AUTHOR]

The article discusses the significant role played by geographic speciation in naming North American ferns, including the taxonomic problems that could likely occur in naming complex plant species where geography has had a major evolutionary role. The author points out that geographic speciation is one of the most important factors in developing a classification that indicates the evolution of a group. Meanwhile, he claims that the taxonomic position of the southern elements of circumpolar fern species need further investigation to verify their present status and to assess their role in the evolutionary history of the species.

The article provides information about the geographical variation of animals. The discovery of the importance of geographical variation and distribution has led to the development of systematics which is applied by all taxonomists. The author defines what are polytypic species and geographical races, including its types and characteristics. Since the process of speciation and race and race-formation depends on different phenomena acting together in different ways, different types of geographical race exist.

The article presents information related to research programs instigated by and accepted into the research organization International Biological Program (IBP) with the purpose of establishing a central focus for the program. Information is given that 12 integrated research programs have been developed by the U.S. National Committee and 240 individual research projects have been accepted by IBP. These integrated research programs include studies related to aerobiology, analysis of ecosystems, Eskimos, and biogeography of sea.

The article reports on the courses related to biological science offered by various associations and universities in the United States. It includes the 1972 course at the W. Alton Jones Cell Science Center located in the Lake Placid, New York; the systems approach to the life sciences at the Utah University together with NSF; and a biogeographical study tour of the Galapagos Islands to be presented by the biology department and the division of continuing education at the University of Colorado Museum in Colorado.