. The Geology of Minnesota . elongate elliptical inoutline, the ventral margin convex but not so much as the dorsal, the ends sub-equally rounded but with the posterior one a little blunter than the anterior; surfacesmooth. This species is readily distinguished from B. cylindrica Hall, by its more equalends and convex basal outline. It seems to be closely related to B. concinna Jones,of the Wenlock shales of England, but the outline is a little different and the valvesthicker in the ventral part. The left valves of Krausella incequalis and K. arcuataare somewhat similar yet not enough so to re
. The Geology of Minnesota . elongate elliptical inoutline, the ventral margin convex but not so much as the dorsal, the ends sub-equally rounded but with the posterior one a little blunter than the anterior; surfacesmooth. This species is readily distinguished from B. cylindrica Hall, by its more equalends and convex basal outline. It seems to be closely related to B. concinna Jones,of the Wenlock shales of England, but the outline is a little different and the valvesthicker in the ventral part. The left valves of Krausella incequalis and K. arcuataare somewhat similar yet not enough so to render confusion between them at alllikely. The species is named for the promising geologist. Dr. Ulysses S. Grant, of theGeological Survey of Minnesota. Formation and locality.—M-iddle third (Rhinidictya bed) of the Trenton shales, St. Paul and Minne-apolis, Minnesota. * Ann. Mag. Nat. Hist., ser. i, vol. ill, pi. xiv, fig. i; 690 THE PALEONTOLOGY OF (?) ROBUSTA, n. sp. [Bythocypris?
Size: 3300px × 757px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookidgeologyofmin, bookyear1897
