Trichodina kamchatika Konovalov, Shevlyakov et Krasin, 1970 is redescribed based on specimens obtained from the gills and body surface of brook trout (Salvelinus fontinalis) from Nova Scotia and Quebec, Canada and its taxonomic history briefly reviewed. This is the first report of T. kamchatika from North America.
Results are presented from a study of variability in the stellar wind of G8 Cygni [07.5 III((f))], based on 33 lUE high resolution spectra taken over ~ 7 days. Significant changes are evident in the Si IV resonance line profiles on timescales as short as ~ 1 hour, cliaracterised by broad absorption enhancements at relatively low velocity (0.5 to 0.7 of the terminal velocity, υ∞) which evolve into high velocity discrete absorption components (at > 0.8 over a period of ~ 1 day. The recurrence timescale for the appearance of the broad features is ~ 15-20 hours. Three well monitored consecutive sequenccs of progressive opacity enhancements are described. Their properties are parameterised and incorporated into a self-consistent phenomenological model where the opacity enhancements and ‘underlying’ wind sure radiatively coupled.
The model results show that the absorption enhancements do not propagate from the photosphere in any simple way, and are not due to spherically symmetric phenomena. We conclude that the discrete absorption variability in G8 Cyg is not due to ‘shells’ or ‘puffs’ of matter, but instcaid arise from material passing through perturbations in the flow, which may be illustrated in terms of spirally wound-up streams.