The publication dates of the Transactions of the Linnean Society of London,Series I,1791–1875*

Evidence for the dates of publication of the parts of the Transactions of the Linnean Society of London, Series 1,1791–1875, has been collected from the Minute Books of the Linnean Society, the Journal Books of the Royal Society, The Times, Bent's Monthly Literary Advertiser, the Bookseller, the Gardener's Chronicle, and the Athenaeum. Dates have been traced for all parts except five, and two of those may have been issued with other parts that have been dated.     

Characterizing dispersal patterns in a threatened seabird with limited genetic structure

Genetic assignment methods provide an appealing approach for characterizing dispersal patterns on ecological time scales, but require sufficient genetic differentiation to accurately identify migrants and a large enough sample size of migrants to, for example, compare dispersal between sexes or age classes. We demonstrate that assignment methods can be rigorously used to characterize dispersal patterns in a marbled murrelet (Brachyramphus marmoratus) population from central California that numbers approximately 600 individuals and is only moderately differentiated (F_ST～ 0.03) from larger populations to the north. We used coalescent simulations to select a significance level that resulted in a low and approximately equal expected number of type I and II errors and then used this significance level to identify a population of origin for 589 individuals genotyped at 13 microsatellite loci. The proportion of migrants in central California was greatest during winter when 83% of individuals were classified as migrants compared to lower proportions during the breeding (6%) and post‐breeding (8%) seasons. Dispersal was also biased toward young and female individuals, as is typical in birds. Migrants were rarely members of parent‐offspring pairs, suggesting that they contributed few young to the central California population. A greater number of migrants than expected under equilibrium conditions, a lack of individuals with mixed ancestry, and a small number of potential source populations (two), likely allowed us to use assignment methods to rigorously characterize dispersal patterns for a population that was larger and less differentiated than typically thought required for the identification of migrants.     

EARLY–MIDDLE JURASSIC LYTOCERATID AMMONITES WITH CONSTRICTIONS FROM MOROCCO: PALAEOBIOGEOGRAPHICAL AND EVOLUTIONARY IMPLICATIONS

Abstract:  The ammonite genus Alocolytoceras Hyatt, 1900 is an uncommon lytoceratid with distinctive shell ornament. A set of 58 specimens, recently collected at Amellago in the central High Atlas (Morocco), has enabled us to trace a succession of three species over eight biozones from the Toarcian to the Aalenian. Two specimens from the Lusitanian Basin are added for comparison. Following a review of the genus, based on original specimens and data from the literature, seven species are considered valid. A palaeobiogeographical synthesis of 13 regions demonstrates irregular distribution patterns over time, with a constant presence in the south-west Tethys and an instance of rapid diversification of an endemic fauna in north-west Europe. Our data challenge the conventional view that lytoceratid ammonite evolution was 'conservative'.     

Role of Base Composition in the Electrophoresis of Microbial and Crab DNA in Polyacrylamide Gels

Intramolecular heterogeneity of eukaryotic nuclear DNA is shown by main-band and satellite DNAs. The function of the latter is uncertain, but they migrate more slowly in electrophoresis; this seems to be determined by base composition.     

Influence of Light of Different Spectral Compositions on Growth and Metabolism of Citrus Seedlings

Sour orange (Citrus aurantium L.) seedlings grown for six months under covers transmitting light of different spectral composition, were compared with others grown under a white cover (control) and outside in full daylight. The intensity of transmitted light was equalized under all covers and attained only 20% of full daylight. Seedlings grown in daylight were shorter, had more internodes, smaller leaves, less chlorophyll and more ascorbic acid than the others. Blue + far-red covers (no transmission between 560–700 nm) enhanced seedling length, the protein and chlorophyll content and peroxidase activity of leaves. When also the wave-range above 700 nm was cut out (blue) seedlings were the shortest, and leaves had very high protein and chlorophyll content, but much less ascorbic acid and lower peroxidase activity. Red + far-red covers (no transmission below 500 nm) enhanced seedling length more than blue + far-red; leaves contained as much protein as control, but had relatively high chlorophyll and peroxidase activity. Ascorbic acid was as low as in blue light.