. Bulletin - New York State Museum. Science. 182 NEW YORK STATE MUSEUM volutions less than two. There is no evidence of spirality in the body whorl beyond the first third of the shell. Section of body whorl. Platyceras leboutillieri circular. Shell growth somewhat irregular in late stages but ap- parently without nodes. Aperture but slightly undulated. Hight from apex to stoma i8 mm, diameter of body whorl near aperture 14 mm. Lower Devonic. Grande Greve and Perce rock, P. Q. Platyceras gaspense nov. A rather small species with small spiral of one and one half whorls very rapidly expanding so
. Bulletin - New York State Museum. Science. 182 NEW YORK STATE MUSEUM volutions less than two. There is no evidence of spirality in the body whorl beyond the first third of the shell. Section of body whorl. Platyceras leboutillieri circular. Shell growth somewhat irregular in late stages but ap- parently without nodes. Aperture but slightly undulated. Hight from apex to stoma i8 mm, diameter of body whorl near aperture 14 mm. Lower Devonic. Grande Greve and Perce rock, P. Q. Platyceras gaspense nov. A rather small species with small spiral of one and one half whorls very rapidly expanding so that at the end of the one and one half vo- lutions the shell is of notable width; thence the whorl becoming free Platyceras gaspense and suberect, suggesting the outline of P. t h e t i s Hall of the Ham- ilton shales but with*shorter body whorl and larger spire. The final whorl is compressed but appears to have been subelliptical in cross-section. Surface smooth with one or more longitudinal furrows. Middle Devonic. Gaspe Basin, P. Q. Platyceras paxillifer nov. A small shell closely coiled for two and one half volutions or throughout its length, rapidly expanding and having the general as- pect of a shallow Diaphorostoma or Strophostylus; the surface roughly corrugated concentrically, the upper shoulder of the shell bearing a single row of slender spines, beginning, in the best pre- served specimens, at the end of the second whorl or the commence- ment of rapid expansion, and three in number at unequal intervals. This species represents one of the large group of spined Platy- cerata so frequent at this period in the development of the genus;. 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
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectscience, bookyear1887
