CLASS GASTROPODA 
11 
basi elongata, liris spiralibus vi., contiguis ornata; apertura gibbosa; labro 
acuto, interdum varicoso, antice angulatim emarginato; labio tenui. 
Long., 25; long.'spir., 19; lat., 09. poll. (Carpenter.) 
Shell elongate-conic, yellowish white. Nuclear whorls two, well- 
rounded, smooth. Post-nuclear whorls flattened, much wider at the periph¬ 
ery than at the summit, overhanging, ornamented on the first seven 
whorls by four equal and equally spaced spiral cords, of which the pos¬ 
terior is at the summit and the anterior at some little distance above the 
suture; on the last whorl an additional slender cord appears between that 
on the summit and its neighbor. In addition to these spiral cords, the 
whorls are marked by strong, broad, low, axial ribs, of which twelve occur 
upon the first and second, fourteen upon the third and fourth, and sixteen 
upon each of the remaining whorls. The intersections of the spiral cords 
and axial ribs are nodulose. In addition to these cords and ribs, the entire 
surface of the shell is marked by numerous, very fine, spiral striations and 
slender lines of growth. Periphery of the last whorl marked by a sulcus 
which is as wide as the space between the cords on the spire and is crossed 
by the slender continuations of the axial ribs. Base well-rounded, marked 
by eight spiral cords. Aperture elongate, decidedly effuse at the junction 
of the outer and basal lips, channeled anteriorly and subchanneled at the 
posterior angle; outer lip thin, rendered somewhat sinuous by external 
sculpture; columella short and twisted; parietal wall covered with a thick 
callus, which extends over the edge of the columella and renders the 
peritreme complete. In the two specimens before me a strong varix is 
present a fourth of a turn behind the lip. Length, 4.7; diameter, 1.5 mm. 
(Bartsch.) 
Type. Specimen in United States National Museum, No. 162561. Type 
locality, Lower Pleistocene beds at Santa Barbara, California. 
Range. Known only from type locality. 
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Genus ALABINA Dali, 1902 
Shell conic, small, of numerous whorls; aperture oval, outer lip thin, 
columella short, moderately strong, strongly curved and slightly reflected 
at the base. Canal undeveloped. (Oldroyd.) Dr. Dali named the genus but 
did not describe it or cite a type, hence Mesalia tenuisculpta Carpenter, 
1863, the first species mentioned under the new genus, is chosen as the 
type. 
Distribution. California to Lower California. 
[ 613 ] 
