. Bulletin - New York State Museum. Science. Platyceras lejeunii concentric growth lines. The surface is covered with very long and slender spines which are curved or arched backward. The shell is more slender than other echinate species and the spines relatively longer and more arched. Lower Devonic. Grande Greve, P. Q. Platyceras (Orthonychia) belli nov. Shell erect, minutely arched and incurved at the apex, expand- ing very gradually but equally for nearly one half its length and thence more abruptly, the cross-section of the whorls being es-. /â - Platyceras (Orthonychia) belli sentially c
. Bulletin - New York State Museum. Science. Platyceras lejeunii concentric growth lines. The surface is covered with very long and slender spines which are curved or arched backward. The shell is more slender than other echinate species and the spines relatively longer and more arched. Lower Devonic. Grande Greve, P. Q. Platyceras (Orthonychia) belli nov. Shell erect, minutely arched and incurved at the apex, expand- ing very gradually but equally for nearly one half its length and thence more abruptly, the cross-section of the whorls being es-. /â - Platyceras (Orthonychia) belli sentially circular and the stomal margin undulated. Surface crossed transversely by rugose concentric growth lines, their un- dulations corresponding to low grooves and folds of the shell. Length of a full-sized specimen 50 mm; stomal width 33 mm. Lozver Devonic. Grande Greve, P. 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: 1105px × 2262px
Photo credit: © Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectscience, bookyear1887
