Abstract Phosphate-shelled brachiopods differ in filter-feeding lifestyle, with Lingula anatina an active infaunal burrower, and Discinisca tenuis a shallow marine epibenthic animal. The shells of these animals are built organophosphatic constituents, the organic fibres/sheets reinforced calcium phosphate to provide sophisticated ultrastructural robustness. This investigation examined nature fi...

The brachiopoda, Lingula unguis, has a pair of anterior adductors located in the center of the shell. Each muscle consists of an opaque and a translucent portion which is constructed of smooth and obliquely-striated muscle respectively. According to our ultrastructural observations, the opaque portion seems to have two types of cells. They differ only in the diameters of their thick myofilament...

TOPOGRAPHY BETWEEN TROUGHS. D.P. Winebrenner 1,2 , M.R. Koutnik 2 , E.D. Waddington 2 , A.V. Pathare 3 , S. Byrne 4 , and B.C. Murray 5 , 1 Applied Physics Laboratory, University of Washington, Box 355640, Seattle, WA 98195, [email protected] 2 Dept. of Earth and Space Sciences, University of Washington, Box 351310, Seattle, WA 98195, 3 Planetary Science Institute, 1700 E. Fort Lowell Rd.,...