The grey wolf (Canis lupus) was numerous on the Scandinavian peninsula in the early 19th century. However, as a result of intense persecution, the population declined dramatically and was virtually extinct from the peninsula by the 1960s. We examined historical patterns of genetic variability throughout the period of decline, from 1829 to 1979. Contemporary Finnish wolves, considered to be representative of a large eastern wolf population, were used for comparison. Mitochondrial DNA (mtDNA) variability among historical Scandinavian wolves was significantly lower than in Finland while Y chromosome variability was comparable between the two populations. This may suggest that long-distance migration from the east has been male-biased. Importantly though, as the historical population was significantly differentiated from contemporary Finnish wolves, the overall immigration rate to the Scandinavian peninsula appears to have been low. Levels of variability at autosomal microsatellite loci were high by the early 1800s but declined considerably towards the mid-20th century. At this time, approximately 40% of the allelic diversity and 30% of the heterozygosity had been lost. After 1940, however, there is evidence of several immigration events, coinciding with episodes of marked population increase in Russian Karelia and subsequent westwards migration.

Fernholm, B. 1981. Thread cells from the slime glands of hagfish (Myxinidae). Denmark.) -Acta zool. (Stockh.) 6 2 ( 3 ) : 137-145.Scanning electron microscopy and light microscopy demonstrate that the mature thread cells in Eptatretus deani and Myxine glutinosa consist of a single, coiled thread up to 10 cm long. Mature thread cells apparently loose the cell membrane within the slime gland before expulsion. Thus the old idea that rupture of the cell membrane causes the uncoiling in sea water is no longer tenable. If the thread cells are transferred without additional fluid to a microscope slide, no uncoiling occurs until sea water or distilled water is added when the process occurs rapidly; however, in double strength sea water uncoiling is slowed down.In tetrahydrofuran or glycerin there is no uncoiling in 100 % or 50 % solutions; however in 5 % solutions uncoiling occiirs slowly. Thus the availability of adequate amounts of water seeins to be necessary for uncoiling. Presumably, water acts directly on the thread, causing the organelle to straighten and thus uncoil. T h e defensive value of the slime production is discussed.

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In wild populations negative effects from inbreeding are usually difficult to assess. The contemporary Scandinavian wolf population (Canis lupus) was established in 1983. With only three founders this population, with approximately 100 individuals, exhibits lower genetic variability than the neighbouring eastern population. Congenital malformations of the backbone were found in this highly inbred population. This study assesses the frequency and morphology of vertebral malformations within the Scandinavian wolf population and compares this with two reference populations. We discuss the etiology of malformations, how they may affect individuals and viability for the population. The frequencies of lumbosacral transitional vertebrae were higher in the small contemporary population than in the eastern reference population. Certain other defects were not found in the reference populations. This study demonstrates malformations that may have a negative impact on the Scandinavian wolf population and be an indication of inbreeding depression. For the conservation of this endangered population, we assert that immigration of wolves from eastern populations is essential.