. Bulletin - New York State Museum. Science. NIAGARA FALLS AND VICINITY 223 at all marked in cither. Glabella smooth, indistinct, eyes large, round, lateral cheeks small. Thorax usually consisting of 10 seg- ments, with smooth pleurae. Illaenus ioxus Hall (Fig. 154). B u - m a s t i s b a r r i e n s i s Hall (1852. Pal. N. Y. 2:302, pi. 66) Distinguishing characters. Elongate elliptic form; rounded, nearly equal cephalon and pygidium, with the triloba- tion scarcely marked; large eyes near the posterior lateral border of the cephalon; faint trilobation of thorax with very broad central lobe;
. Bulletin - New York State Museum. Science. NIAGARA FALLS AND VICINITY 223 at all marked in cither. Glabella smooth, indistinct, eyes large, round, lateral cheeks small. Thorax usually consisting of 10 seg- ments, with smooth pleurae. Illaenus ioxus Hall (Fig. 154). B u - m a s t i s b a r r i e n s i s Hall (1852. Pal. N. Y. 2:302, pi. 66) Distinguishing characters. Elongate elliptic form; rounded, nearly equal cephalon and pygidium, with the triloba- tion scarcely marked; large eyes near the posterior lateral border of the cephalon; faint trilobation of thorax with very broad central lobe; granulose or punc- tate surface. Found in the Clinton limestone lenses in great abundance, usually represented only by cephala and pygidia. These Fig. 154 luaenus ioxus are often crowded together in great profusion to the exclusion of nearly every other fossil. Also found rarely in the lower and middle Roches- ter shale at Niagara. Also found at Lockport and elsewhere (Hall).. /, Genus dalmanites Barrande [Ety.: proper name] (1852. Systcnic sihiricn Boh. v. i) Cephalon distinctly trilobate, with a large glabella and prolonged lateral or genal spines; glabella tumid, widest in front, and divided by three well marked lateral furrows; facial suture extending from in front of the genal angles in- ward to the eyes and thence forward around the glabella; eyes large, with numerous distinct lenses. Thorax of II segments with grooved pleurae. Pygidium large, of many segments, triangular and often pointed or extended into a mucronate termination. Fig. 155 Dalmanites limulurus. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original New York State Museum; New York State Museum. Albany : New York State Education Dept
Size: 1200px × 2083px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectscience, bookyear1887
