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The article discusses the study which assesses the evidence from British hepatics with discontinuous distribution outside the British Isles in relation to the history of the British flora. In this paper, British hepatics showing disjunction in their world distribution are classified in six groups including mediterranean element, disjunct-temperate element and the American element. It is concluded that the hepatics considered do not form a homogeneous group and their distribution patterns all appear to be explicable in terms of post-glacial climatic change without invoking in situ survival through glaciation.

The article presents studies on the vegetation of Nottinghamshire, England. This paper explored the geological structure of the ecology of the Bunter Sandstone and superficial deposits. Different conditions were also taken into account including the climatic and edaphic focusing on the flora of the Sherwood forest. Different plant communities were subjected for thorough investigation recording the botanical information and general account of vegetation. The result of the experiment is discussed in brief.

The article presents information about several papers on social history of the Medieval period. Bringing together from the Pergamenos collection of the Archives of the Crown of Aragon 91 documents concerning the Vivas family of Provençals, a neighboring village to Barcelona, Spain between the years 986 and 1084, M. Pierre Bonnassie has been able to follow, with a precise detail very rare for this period and with a considerable insight, the rise of a well-to-do peasant family entering the ranks of the aristocracy. M. Georges Duby, for his part, has studied "Au Xlle siècle: les "jeunes" dans la société aristocratique." He shows that the fate of this horde abandoned to the conquest of glory, profit and female prey by noble houses wishing to relieve the excess of their expansive power, a group very prone to violent death, is not without interest for economic history. In his paper, Mile Emilienne Demougeot has tried to trace a relation between climatic variations and invasions, those invasions at least which occurred in the West up to that of the Cimbrians, Teutons and Goths, at the end of the second century B.C.

The article describes the microclimates of the Olokemeji Forest Reserve as a prelude to studies on seasonal changes in the vegetation in Nigeria. This description is based on rainfall and temperature data from Olokemeji and for other climatic elements, on data from Ibadan. The mean length of dry periods is less than 4 days during the wet season and rises to over 50 days during the dry season. The results show that Olokemeji has a climate typical of it area of the country and of the forest/derived savanna boundary area in west Africa.

The article discusses the evolution of modern plant ecology in Great Britain. According to the author, the foundations were laid earlier and the conceptions of plant formations were developed by famous phytogeographers as Humboldt and Grisebach in the first half of the century. Furthermore, its modern meaning was determined by the publication of Warming in 1895 on "Plantesamfund: Grundträk af den ökologiske Plantegeografi." It was translated into German and widely used in England and America which it played as an important part in stimulating fieldwork for both countries. In 1898, A. F. W. Schimper published "Pflanzengeographie auf physiologischer Grundlage," which focus on the types of vegetation throughout the world and discusses the climatic and edaphic factors.

Pollen analysis of three sites on Wilsons Promontory provides a vegetation record from 6000 B.P. to the present day. No extensive changes in the vegetation have been found over this time period, but local and regional variations in the extent of communities may imply small climatic changes. Moister conditions than at present seem to have prevailed earlier than 4500 B.P., followed by a drier phase till less than 2000 B.P., when an increase in moisture gave conditions similar to those of today. Some evidence exists to support the theory of a relatively steady sea level close to the present level over the last 6000 years along the western Wilsons Promontory coastline. [ABSTRACT FROM AUTHOR]

The article reports on the Becium homblei as a plant with high copper soils in Central Africa. Becium homblei is a plant which endure soil copper concentrations of up to 15,000 ppm and endure soil nickel concentrations of about 5,000 ppm. It is found on areas where soil metals are abundant and soil bases specially calcium are low. It is limited by climatic boundaries such as soil pH, soil metal content, and soil calcium bases. It is also widely distributed in Central Africa due to biotype depletion caused by climatic change.

The article focuses on the utilization of Wilm's method to explain the underlying principles in the collection and statistical treatment of climatic data. It cites that the method is used to determine several chemical elements found in the throughfall data, such as the suspension of bryophyte ground layer in the gauges and approximation of the variance of temperature and humidity data. It also mentions that the changes in the utilization of the method are based on the consideration of the regression line in the data analysis. Further, information on the statistical techniques and methods of computation for the result is also included.

The article examines some problems of mid-Post-glacial ecology and chronology in the area south and east of the English Lake District in England. The post-glacial increase in pine pollen frequencies is discussed. The stratigraphical evidence for changes in water level during mid-Post-glacial times is detailed. Information on the radiocarbon evidence from Lonsdale is presented. A discussion is presented on the relation of pine maximum in Lonsdale to local habitat factors and the climatic implications of the pine maximum in Lonsdale.

The article describes the microclimates of forest and savanna sites in the Olokemeji Forest Reserve in Nigeria. This description is based on rainfall and temperature data from Olokemeji and for other climatic elements, on data from Ibadan. The mean length of dry periods is less than 4 days during the wet season and rises to over 50 days during the dry season. The results show that Olokemeji has a climate typical of it area of the country and of the forest/derived savanna boundary area in west Africa.

The article examines the study of vegetational history of post-glacial period in Great Britain. The data from stratigraphy shows that plant remains and the pollen analyses from the site contain lake muds such as Betula, Pinus and Salix. During the Late-glacial period, there was an evidence of a cold climate and of a vegetation of open birch woodland or open vegetation with copses and a rich herbaceous ground flora as well. Thus, the evidence for a climatic oscillation marked a general climatic amelioration of the Post-glacial period.

The article focuses on a study regarding the plant communities on the northern slopes of the island of Pico in the Azores. It mentions the climatic conditions prevailing in the Azores' islands which are characterized by frequent mists, strong winds and a high rate of rainfall. It states that the Pico island is formed entirely of alkali basalt or olivine, and its northern slopes, the Baldios do Conselho, are less steeper than the slopes in the south and are covered with woodland. The assumed dominance of the Pittosporum undulatum tree has affected the vegetation of the northern slopes of Pico which has further resulted in a complex of vegetation.

The article discusses the study which aims to set on record results of a phenological survey accomplished in conjunction with a local climatic survey in Bath, England during 1945 and 1946. Bath is situated where Avon lessens the gap in the escarpment of the Cotswold Hills and is the center where six valleys developed on the dip slope of the escarpment. Proximity to water, soil type and vegetation cover are factors in local climatology that may locally be dominant and their effects need specific measurement. It is concluded that local variations of temperature are significant in producing local variations of plant growth.

The article outlines the research conducted on the vegetation in Mauritius. Researchers found that the mean annual rainfall over the upland climax forest is of the order of 3175 millimeters and the nearest site where records are available over a long period is at Curepipe Gardens. Another important factor that affect the metabolism of the living organism is the intensity of rainfall from day to day. Knowledge of such distribution would enable them to have a better appraisal of the real wetness or dryness of the site. Discussed are the details of the issue.

The article presents a study of the charcoals obtained from the recent excavations on the Maiden Castle, England and their significance in relation to the vegetation and climatic conditions in prehistoric period. A few specimens of charcoal collected from the site indicated that the wood was partially decayed before carbonizing. The specimens of charcoals were examined from Neolithic, Early Iron Age and Late Iron Age deposits from the site. It was evident that in Neolithic times, the chalk of Dorset was clothed with a closed plant community of woodland. It was observed that composition of plant species were changing slightly in all the three periods and the soil conditions were becoming less favorable for the growth of oak.

The article focuses on the endemic trees of the British Guiana Peneplain. It describes the situation, climate and topography British Guiana and the distribution of the main climatic associations. It also notes the influence of climate on the distribution of other species and the prevalence of endemism in the Guiana flora through the analysis of the local and general range of forty of the commonest trees. It also states the likelihood of the endemic species of the Guiana flora which have evolved in the highlands that borders the western and southern limits of the peneplain.

The article highlights a report discussing the pleistocene climatic changes and the distribution of life in East Africa. It reports that the present evergreen forest boundaries are generally not natural, noting that they have been reduced by human agency as much as they would have been appreciable drop in rainfall. It discusses the changes that have occurred in the West African forest for a period prior to 400,000 thousand years ago. It also examines the impact of the subsequent dry period in the areas including Elgon, Kilimanjaro, and the highland forms in Southern Tanganyika Territory.

The article offers information on the prevalence of vivipary on the sea shore. It is cited that one of the features of the mangrove forests is the habit of germination of the seeds on the parent trees. It is said that some refer to vivipary as a relic from the past under the uniform climatic conditions, while others regard it as an adaptation to environment, providing the species with a means for dispersal. It is mentioned that viviparous habit could start the growth of roots in the soil, thus, viviparous seeds should establish themselves on a tidal coast.

Describes environmental requirements for germination and flowering, and the pattern of leaf and tiller development in contrasting light and temperature regimes in collections of forage grass. Materials used in the study conducted on the climatic variation of forage grasses; Description of the effect of temperature on percentage and rate of germination; Genetic variation and effect on flowering behavior.

Examines the impact of climatic variation on leaf development in forage grasses Lolium perenne and Dactylis glomerata. Climatic races of Lolium perenne and Dactylis glomerata; Influence of temperature and supplementary lighting on leaf expansion; Utility of the pattern of climatic variation in the forage grasses in crop improvement.