Fresh-Water Ectoprocta: Distribution and Ecology of Five Species in Southeastern Louisiana

Abstract

covered. One should experiment with preparing both glycerine and permanent mounts. The problem here is getting the right amount of glycerine or permanent mount- ing medium in the well. Too little causes bubbles or air pockets; too much will run out over the sides of the coverglass, preventing sealing. In some cases it is better to have higher well sides or walls for observing either water or glycerine mounts. Two or more layers of plastic are acceptable for powers up to 400 X. EVERITT, B. 1975. Fresh-water Ectoprocta: distribution and ecology of five species in southeastern Louisiana. Trans. Amer. Micros. Soc., 94: 130-134. Species collected are Victorella pavida, Pottisiella erecta, Fredericella sultana, Plumatella repens, and Pectinatella magnifica. Colonies were collected from 59 localities in 10 parishes, and physicochemical data were recorded. Distribution was considered with respect to the physicochemical characteristics of the habitats. No published records of fresh-water ectoprocts exist for Louisiana, although several species have been collected in nearby states. Jullien (1885) referred to Pectinatella magnifica collected in Mississippi. Wurtz & Roback (1955) recorded Plumatella repens, Nolella sp., and the entoproct Urnatella gracilis from the Neches and Sabine Rivers in Texas. Rogick (1959) cited records of Pottsiella erecta from Lake Dallas, Texas. Dendy (1963) reported Plumatella repens, P. casmiana, and Pectinatella magnifica in Alabama. The objectives of this study were to record the distribution of fresh-water ectoprocts in ecologically different localities in southeastern Louisiana and to consider possible relationships between species distributions and the physico- chemical characteristics of the habitats studied. covered. One should experiment with preparing both glycerine and permanent mounts. The problem here is getting the right amount of glycerine or permanent mount- ing medium in the well. Too little causes bubbles or air pockets; too much will run out over the sides of the coverglass, preventing sealing. In some cases it is better to have higher well sides or walls for observing either water or glycerine mounts. Two or more layers of plastic are acceptable for powers up to 400 X.