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Die Wachstumsperiode des Frühjahres 1933 mit den schnellen, großen Schwankungen von Temperatur und Wetter, oft innerhalb weniger Stunden, zeigte bei vielen Pflanzen der Olmützer Flora die verschiedensten Verkrümmungen, Schrurnpfungen, Verfärbungen an Blatt und Blüte. Die Ursache davon war eine Art Verkühlung (Unterkühlung), hervorgerufen durch den genannten Witterungscharakter. Als Folgen dieser Erkältungen, die beim Erfrieren der Pflanze den Höchstgrad erreichen, stellen sich vielfach Änderungen des normalen chemisch-physiologischen Wachstumsprozesses, aber auch Änderungen des normalen physikalischen Gleichgewichtszustandes im Gewebe ein: so erfolgt eine Reduktion des Atmungsprozesses, die Einstellung oder Verminderung synthetischer Aufbauprozesse (Chlorophyll!), Zerfall der Proteine in N-haltige Spaltungsprodukte, weiters Kälte-Kontraktion des Lellprotoplasmas, Plasmolyse, Änderung des colloidalen Zellinhaltes u. v. m. Besonders die schnell einsetzende, längere, große Unterkühlung nach warmen Tagen bewirkt unter Anderem bei der wachsenden Pflanze ein starkes Zusammenziehen des Primordialschlauches der Zelle und damit ein unregelmäßiges, mehr oder minder großes Durchtreten des Zellwassers in die Interzellularräume des Pflanzengewebes. Die dadurch notwendig entstehenden abnormen, oft einseitigen Druck- und Spannungsänderungen im Gewebsparenchym sind es nun hauptsächlich, die sich - in Verbildung der normalen Organform der Pflanze - als zeitweilige Verkrümmungen, Wellungen, Schrumpfungen , Verfärbungen u. ä. verraten, später aber wieder ausgleichen, wenn normale Wachstumsbedingungen eintreten. Die typischen Formen solcher „ Wettersiörungen" des Wachstums der Pflanzen - die "Verkühlung der Pflanze" und der "Kälte-Ikterus" - seien unter Nr. 655 u. 656 dieser Abhandlung - (VI. Teil) näher erwähnt. Über weitere publizierte Krankheiten und Mißbildungen an Pflanzen der Olmützer Flora siehe: Nr. 1-271, (1. T.), Jg. 36, 1925, cas. Vlast. spol. Mus. v Olumouci, Nr. 272-331, T.), Jg. 38, 1927, s.o. Nr. 332-440, T.), Jg. 62, 1931, Verh. des Naturf. Ver. in Brünn. Nr. 441-550, (4. T.), Jg. 63, 1932, s.o. Nr. 55 1-650, (5. T.), Jg. 64, 1933, s.o. Nr. 651-750, (6. T.), Jg. 65, 1934, s.o.
The impact of naval sonar on beaked whales is of increasing concern. In recent years the presence of gas and fat embolism consistent with decompression sickness (DCS) has been reported through postmortem analyses on beaked whales that stranded in connection with naval sonar exercises. In the present study, we use basic principles of diving physiology to model nitrogen tension and bubble growth in several tissue compartments during normal div ng behavior and for several hypothetical dive profiles to assess the risk of DCS. Assuming that normal diving does not cause nitrogen tensions in excess of those shown to be safe for odontocetes, the modeling indicates that repetitive shallow dives, perhaps as a consequence of an extended avoidance reaction to sonar sound, can indeed pose a risk for DCS and that this risk should increase with the duration of the response. If the model is correct, then limiting the duration of sonar exposure to minimize the duration of any avoidance reaction therefore has the potential to reduce the risk of DCS.
As a preliminary step towards a more intensive research on the diversity of macromycetes in Greece, an updated check-list of the Greek mycoflora is presented together with information on the host-substrates and geographic occurrence. The data originated from a thorough literature search and the authors' field observations. In total, 58 families, 214 genera and 811 species of fungi are recorded belonging to Basidiomycetes. The systematics and nomenclature of the relative bibliography have been updated and suitably revised. The large gaps in our knowledge on the existence and distribution of higher fungi in Greece are emphasized.
The cirripeds sampled by the N. O. Jean Charcot from the Azores region include thirty-four species: twenty lepadomorphs, eight verrucomorphs and six balanomorphs. Among these are two new species: Arcoscalpellum eponkos n.sp. and Tesseropora arnoldi n.sp. and several little known species. The family Verrucidae is revised, and a key to the genera is included. Verruca and Metaverruca are rediagnosed, two new genera are proposed: Newmaniuerruca n.g. and Costatoverruca n.g. A list of recent species of Verrucidae is provided, reported with keys to all of the species. Forty-five species of cirripeds are reported from the Azores region, of which one third are endemic.
The specimens which form the basis of the following notes and descriptions were received by the writer from Mr. Ch'i Ho, Asistant Entomologist of Fan Memorial Institute of Biology, who collected thern either in Peiping or Eastern Tomb (40.2 N, 117.0 E), Hopei Province. They belong to nineteen species and are included in fifteen genera. Two of the species are believed to be new to science.
Birds are characterized by pneumatization of their skeletons by epithelial diverticula from larger, air-filled cavities. The diverticula-or 'air sacs'-that invade the postcranium result from outgrowths of the lungs; poslcranial pneumaticity has been very well studied. Much more poorly understood are the air sacs that pneumatize the skull. Study or craniofacial pneumaticity in modern birds (Neornithes) indicates the presence of two separate systems: nasal pneumaticity and tympanic pneumaticity, The lacrimal and maxillary bones arc pneumatized by diverticula of the main paranasal cavity, the antorbital sinus. There are five tympanic diverticula in neornithines that pneumatize the quadrate, articulare and the bones of the braincase. The pneumatic features of the following six genera of Mesozoic birds are examined: Archaeopteryx, Ellaliornis, Baplomis, Parahesperornis, Hesperornis and lchthyornis. Despite the 'archaic' aspect of most of these birds, many of the pneumatic features of neornithines are found in .Mesozoic birds and are considered primitive for Aves. The phylogenetic levels at which most of the avian pneumatic features arose within Archosauria are uncertain. Until the phylogenetic levels at which homologous pneumatic features arose are determined, it is unwise to use most pneumatic characters in the discussion of avian origins. Within avian phylogeny, Ornithurae and Neornithes are well-supported by pneumatic synapomorphies. There is a trend towards reduction of craniofacial pneumaticity within Hesperornithiformes. Witthin Neornithes, four derived pneumatic characters suggest that the Palaeognathae (ratites and tinamous) is monophyletic.