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An intensive seasonal sampling programme at twocontrasting sites in Loch Lomond, the largest lake inBritain, showed the 1992–93 status of the loch to bemesotrophic in the shallow south basin andoligotrophic in the deeper north basin. There isevidence for an increase in both phytoplanktonproduction and reactive phosphorus concentrations inthe loch during the two decades up to 1993. CanonicalCorrespondence Analysis (CCA), plus classification (by Two-Way Indicator Species Analysis: TWINSPAN) ofthe dataset of time-position samples from the lochrevealed that seasonal factors (particularly thethermal regime of the loch, and associated variables)remain more important than non-seasonal environmentalvariables in predicting changes in phytoplanktoncommunity composition. As in the 1970s, the communityremains dominated by a diatom-desmid assemblage, but cyanobacteria blooms, albeit at fairly low abundance,are becoming a frequent phenomenon in the south basinof the loch.

Parapatellar pain is a common complaint in the active adolescent patient population. Patello-femoral pain syndrome, Osgood-Schlatter disease, Sinding-Larsen-Johansson syndrome, patellar tendinitis, and other stress failure conditions are the primary causes of these parapatellar symptoms. Not all cases of knee discomfort are related to knee pathology. This case study discusses hip pathology as a source of referred knee pain in an 8-year-old male athlete. Care must be taken to evaluate all possible sources of both primary and referred pain in all cases.

The Hadrynian Horsethief Creek Group that underlies much of the northern Selkirk Mountains is divided into three members. The upper pelitic member is overlain by latest Hadrynian to Lower Cambrian rocks of the Hamill Group and is correlated with the Yankee Belle Formation of the Cariboo Group in the Cariboo Mountains to the northwest. The underlying middle marble member is correlated with the Cunningham Formation, and the lowest exposed lower pelitic member with the Isaac Formation.Westward thickening of the Horsethief Creek Group is paralleled by a gradational change in the upper pelitic member from a predominantly clastic sequence to the east to a predominantly calcareous sequence to the west. The overlying Hamill Group also changes in character, becoming more pelitic and interdigitating with basaltic metavolcanics toward the west. These facies changes are compatible with results from adjacent areas that point to deposition on a continental shelf in late Proterozoic to early Paleozoic time.

A glacial dispersal train of erratics derived from Paleozoic bedrock has been delineated stretching east-northeast–west-southwest across central Baffin Island. The lithologies of these erratics suggest a derivation from strata of member B of the Ordovician Ship Point Formation to the west, which are presently either submerged or covered by Quaternary sediment in the eastern part of Foxe Basin. These Paleozoic erratics were carried from Foxe Basin onto the Baffin Upland and the western edge of the Davis Highlands. They can be inferred to have reached at least Ekalugad Fiord and the eastern part of Home Bay.

Phytosociological studies have dealt primarily witlh non-spatial relationships of different types of vegetation and have related the calculated patterns onily secondarily to environmental gradients. Vegetation composition gave the basis for its arrangement in a continuum (Curtis 1959) and for the correlation of associations and other communities (Ellenberg 1956). Studies in plant geography have been concerned mainly with the all-or-nothing approach of plotting distribution maps of taxa. Few botanists have investigated the varying importance of a taxon within its range (Halliday and Brown 1943). Boyko (1947) applied the term geoecology to a combination of phytoisociology and plant geography. He formulated a geoecological law based on autecological studies and indicated possibilities of using environmental criteria for the ordination of vegetation on a quantitative basis. Differences in the environment of two points are so varied that no single environmental factor can be studied without interference of other factors, and it is impossible to state with certainty what constitutes a single factor (Cain 1944). Only variations of groups of factors, termed complex-gradients by Whittaker (1954), are suitable for this approach. Vegetation changes continually over a large area but varies rather abruptly within small areas (Gleason 1926). This pattern suggests the use of two complex-gradients, one of the macro-environment given through geographical position and the other of the micro-environment correlated with local topography, although these gradients are only relative and differ mainly in scale. Whittaker (1956) has used a two-dimensional gradient by plotting macro-environment as altitude against micro-environment which he derived from the vegetation composition. The micro-environmental gradient has only been correlated empirically with the topography. Similar but mostly qualitative comparisons of vegetation on a much greater scale in the ordination of macro-environment against micro-environment were made by Humboldt (1807) and subsequent