Manganese in the tissues of normal animals may be regarded as a rare element. In traces it is known to be present in a number of marine animals, as was shown by Pichard.’ Hoppe-Seyler2 is authority for the statement that it is not infrequently present in human blood and in the liver: but it is neither constant in its occurrence nor significant in amount. Among the lower animals there is at leas...

Surficial (oxic) sediments, overlying water, and specimens of the freshwater bivalve Anodonta grandis were collected by divers at 11 littoral lacustrine sites located along a geochemical gradient of pH, [Cd], Dl, and [Z n in an area influenced by mining and smelting activities. The molluscs were dissected (gills; 1 hepatopancreas; remaining tissues) and analyzed for Cd, Cu, Zn, and metallothion...

Abstract Non-indigenous freshwater bivalves negatively affect invaded ecosystems through different mechanisms, including inter-specific competition for trophic resources. Here, we investigated in Lake Trasimeno (Central Italy) the diet of invasive Dreissena polymorpha and native Anodonta anatina . ? 15 N 13 C stable isotopes were measured winter summer bivalves, phytoplankton, sedimentary organ...

CactusWorld 2016 Vol. 34 (3) Aloe is a large genus of over 500 species (Carter et al, 2011) and even today that number continues to increase. Of these, a very small number of species, perhaps no more than 20, are unusual in having hairy flowers. These are concentrated in southern Arabia and the Horn of Africa. In respect of Saudi Arabia, for example, Collenette (1999) records 22 species of Aloe...