New Archaeoscyphia (Porifera) from the Ordovician of Anticosti Island, Quebec / J. Keith Rigby -- and Matthew H. Nitecki --.

v.33:no.1(1973)

Bibliographic index of North American archaeocyathids / [by] Matthew H. Nitecki --

v.17:no.2(1967)

Quantitative composition and distribution of the silt fraction in surface sediments of the North-West African continental margin

Surface sediments from the continental slope and rise of North-West Africa between the Canary lslands and the Cape Verde Islands are mainly composed of silt-sized material (2-63 µm). A number of sampling profiles were run normal to the coast and the composition of the silt fraction was determined quantitatively by scanning electron microscope analysis. The carbonate portion of the sediment was found to be nearly exclusively of biogenic origin. The most important contributors are planktonic foraminifers and coccoliths with minor contributions derived from pteropods. Plankton-produced biogenic opal such as diatoms and radiolarians play a very minor role. The high production rates of opal-silica plankton which exists in the surface waters of the NW-African upwelling system does not give rise to corresponding increases of opal accumulation in the bottom sediment. Benthic producers consist mainly of foraminifers and molluscs but the entire input from benthic producers is extremely small. An exception to this occurs in the prodelta sediments of the Senegal river. Downslope particle transport is indicated by the occurrence of shallow-water coralline algae, ascidian sclerites and cliona boring chips and can be traced as far down as the continental rise. The non-carbonate silt fraction mostly consists of quartz which is derived as eolian dust from the Sahara desert by the Harmattan and the NE-Trade-wind system. The percentage of carbonate in the surface sediments directly indicates the relative proportions of autochthonous biogenic components and terrigenous allochthonous quartz particles.

Microsatellite genotyping of Mediterranean population of Ircinia fasciculata and Ircinia variabilis

Recent episodes of mass mortalities in the Mediterranean Sea have been reported for the closely related marine sponges Ircinia fasciculata and I. variabilis, which live in sympatry. In this context, the assessment of the genetic diversity, bottlenecks and connectivity of these sponges has become urgent in order to evaluate the potential effects of mass mortalities on their latitudinal range. Our study aims to establish 1.) the genetic structure, connectivity, and signs of bottlenecks across the populations of I. fasciculata, and 2.) the hybridization levels between I. fasciculata and I. variabilis. To accomplish the first objective, 194 individuals of I. fasciculata from 12 locations across the Mediterranean were genotyped at 14 microsatellite loci. For the second objective, mitochondrial cytochrome c oxidase subunit I sequences of 16 individuals from both species were analyzed along with genotypes at 12 microsatellite loci of 40 individuals coexisting in 3 Mediterranean populations. We detected strong genetic structure along the Mediterranean for I. fasciculata, with high levels of inbreeding in all locations and bottleneck signs in most locations. Oceanographic barriers like the Almeria-Oran front, North-Balearic front, and the Ligurian-Thyrrenian barrier seem to be impeding gene flow for I. fasciculata, adding population divergence to the pattern of isolation by distance derived from the low dispersal abilities of sponge larvae. Hybridization between both species occurred in some populations, which might be increasing genetic diversity and somewhat palliating the genetic loss caused by population decimation in I. fasciculata

University of Michigan Women's Golf Team, 1988/89

Back Row: Jennifer Boring, :Lisa Mahnke, Erica Zonder, Mary Hartman, head coach Sue LeClair

Front Row: Kimberly Schlaff, Kristen Beilstein, Becky Hayes, Darcy Chandler

University of Michigan Women's Golf Team, 1989/90

Back Row: Carrie Nosanchuk, Jennifer Tejada, Mary Hartman, Erica Zonder, Tricia Good, Lisa Mahnke, Maura Hawkins, head coach Sue LeClair

Front Row: Jennifer Boring, Wendy Bigler, Kristen Bielstein, Darcy Chandler, Becky Hayes

University of Michigan Women's Golf Team, 1991/92

Maura Hawkins, Kate Hanson, Wendy Bigler, Tegan McCorkel, Patricia Good, Coach Sue LeClair, Erica Zonder, Tiffany McCorkel, Jenny Boring, Kirsten Woodson, Jenny Zimmerman, Carrie Nosanchuk,

Christmas mystery.

Mode of access: Internet.

Irrigation wells and well drilling /

Mode of access: Internet.

The Cambridge natural history,

Vols. 1, 2, 5-7, 9 reprinted 1922; v. 3, 1927; and vols. 4, 8, 10, 1923.

Drilled shafts for bridge foundations /

"August 1993."

Spongiaires.

Cover-title.

Diamond drilling in the southern Black Hills, Fall River County, South Dakota /

"October 1955."

Drilling report, Wind River Basin Project no. 1, Gas Hills area, Wyoming.

"January 1956."

Suggested unit course in drill press work for beginners in machine shop practice ...

Prepared by Ewald L. Witzel and C. Thomas Olivo. cf. 5th prelim. leaf.