. The Conchologists' exchange. Mollusks. 10 THE NAUTILUS. shouldered above the median keel. Covered with an olive epi- dermis. Surface marked by delicate growth-lines and excessively fine, close spiral stria?'. Alt. 5*2, diam. 3 mill; alt. of apert., 2, width 1-3 mill. Lake Patzcuaro, West Mexico. This species is very different from other American Amnicoloids. {To be continued?) DESCRIPTION OF A NEW SPECIES OF HYALINA. BY WM. H. Dr. V. Sterki, of New Philadelphia, Ohio, has of late years been giving special attention to the minute forms of Pulmonata, Vertigo, Papilla, Hyalina, etc. In 1
. The Conchologists' exchange. Mollusks. 10 THE NAUTILUS. shouldered above the median keel. Covered with an olive epi- dermis. Surface marked by delicate growth-lines and excessively fine, close spiral stria?'. Alt. 5*2, diam. 3 mill; alt. of apert., 2, width 1-3 mill. Lake Patzcuaro, West Mexico. This species is very different from other American Amnicoloids. {To be continued?) DESCRIPTION OF A NEW SPECIES OF HYALINA. BY WM. H. Dr. V. Sterki, of New Philadelphia, Ohio, has of late years been giving special attention to the minute forms of Pulmonata, Vertigo, Papilla, Hyalina, etc. In 1886 he collected a small Zonites, of the section Hyalina or Conulus, which, being submitted to several naturalists, appeared to be a new species, although of remarkably small size. In 1887 a few more specimens were obtained, which he has submitted to me with the request that I describe them. Shell minute, thin, yellowish translucent, brilliant, lines of growth hardly noticeable, spire depressed, four-whorled ; whorls rounded, base flattened, somewhat excavated about the cen- ter, which is imperforate; aperture wide, hardly oblique, not very high, semilunate, sharp edged, the upper part of the columella slightly reflected ; upper surface of the whorls roundish, though the spire as a whole is depressed. Max. diameter inch (line a—b, Fig. 1) ; alt. 0*026 inch. This little shell is clearly not the young of a Papilla or of any of our other small Zonites. It is certainly the smallest American species. H. parvula Rang, from Cape Verde Islands, has a little less diameter, but is higher in the spire. H pygmwa and H. mi?iutissima Lea are decidedly larger, besides belonging to a different group. It is probably one of the smallest species known, and remarkable for its imperforate 1 From Proceedings U. S. National Museum, vol. xi, 1888, p. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - co
Size: 1000px × 2500px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1880, booksubjectmollusks, bookyear188
