54 THE NAUTILUS. 
bb. umbilicus small, deep. 
e. lip thickened within, centervillensis Tryon. 
cc. lip simple, thin. 
d. whorls angular above the middle, di/atatus Gld. 
dd. whorls rounded or angular below the middle. 
eé. Spire sunken in center, deflectus Say. 
ee. spire level, apex not sunken. 
um bilicatellus pl. 
Planorbis callioglyptus n. sp. ~ MW enaotle s Ag eee Vaso yw GA (bis 
Shell thin, yellowish corneous. Upper side flat, only a trifle con- Gexl| 
cave in the middle; lower side convex; periphery very bluntly in- 
distinctly angular, and midway between periphery and suture there 
is a slight angle; but both angles are obsolete at aperture; base 
often spirally malleated. Surface with a beautiful sculpture of fine 
spiral incised lines, crenulated by fine growth-lines. Whorls nearly 
4. Umbilicus nearly a third the shell’s diameter, deep and funnel- 
shaped, its edge bluntly angular. Aperture ovate truncate, mod- 
erately oblique. Lip not thickened inside. Alt. 3, diam. 8 mm. 
Freeport, Washington, collected by H. Hemphill. ; 
Planorbis opercularis var. oregonensis n. v. v L open abe ANAABK Le, > Fen 
Shell light yellowish, opaque. Upper surface flattened, aight \eg 
convex, the apex sunken; periphery keeled with a slight groove Be 
above the keel. Surface finely spirally striated. Umbilicus rather 
small and deep, its edge slightly angular. Aperture approaching 
vertical, lip thickenad within. Alt. 2, diam. 6 mm. 
Salem and Portland, Oregon. This looks very much like typical 
opercularis, but may be distinguished by the beautiful spiral sculp- 
ture and thickening within the lip. It differs from callioglyptus in 
having a decided keel around the nearly flat upper surface and a 
distinct thickening within the aperture. I have not seen any typical 
P. opercularis from Oregon. There are none in the collection of 
the Academy of Natural Sciences. 
SYNONYMS. 
P. billingsii Lea = parvus Say. 
P. brogniartiana Lea = exacutus Say. 
P. buchanensis Lea = exacutus Say (fide Simpson). 
P. circumstriatus Tryon = parvus Say. 
P. concavus Anth., M.S.= parvus Say. 
, 1 A 
P. costatus DeTarr & Beecher = P. nautileus var. cristatus Drap. 
