46 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
and the sutures more constricted. This is the most northern form. Height 
of shell, 31; of last whorl, 24; of aperture, 19; breadth, 16.5 mm. (Dali.) 
Type in United States National Museum. Type locality, Sitka, Alaska. 
Range. Sitka, Alaska, to Puget Sound, Washington. 
Thais canaliculata Duclos, 1832 
Plate 35, figs. 3, 4 
Annales des Sciences Naturclles, 26: 104; PI. 1, fig. 1. 
Cette espece voisine de Purpura succincta de M. de Lamarck's en 
distingue eminemment par sa taille plus petite, plus elancee, par ses cor- 
delettes plus fines et sa couleur rougeatre. Eile est oblongue striee pro- 
fondement dans toute sa longueur, et de plus ornee d’un canal spiral forte- 
ment prononce que ne se rencontre que dabs deus especes du meme genre. 
La columelle est lisse, blanche, legerement aplatie; le bord gauche est uni 
a Tinterieur et de teinte rosee, le test mince. Long., 16 lignes. (Duclos.) 
Shell bucciniform, of three and a half to four rounded whorls ex¬ 
clusive of the nucleus, moderately thick, with a spire about one-half 
shorter than the aperture, the last whorl largest, with a very uniform 
sculpture of strong elevated spiral ridges separated by distinctly channeled 
interspaces crossed by small slightly elevated axial lamellae or elevated 
lines; minor spirals very rarely occur; there are 4 to 6 major spirals on the 
penultimate whorl and about 10 on the last whorl; outer lip not reflected 
and only slightly thickened, usually crenulated by the external sculpture; 
pillar moderately arcuate, flattened in front where the callus conceals but 
does not seal a long narrow umbilical chink; canal narrow, recurved. 
(Dali.) 
Type in Museum Paris. Type locality, California. 
Range. The whole Aleutian chain, eastward to Sitka and southward 
to Monterey, California. 
Thais canaliculata analoga Forbes, 1850 
Plate 35, fig. 1 
Proceedings , Zoological Society of London, 275; PI. 11, fig. 12. 
P. testa turrita, albida, spiraliter late rufo-fasciata; spira exserta; 
anfractibus 5 rotundatis, costis spiralibus (6 ad 8 in anfractu penultimo), 
quadratis, numerosis cinctis, interstitiis crenulatis, ad suturam obsoletis 
labro subdenticulato. Long., 1 4/12; lat., 8/12; long, apert., 8/12 unc. 
Similar to the preceding but stouter, usually with one more whorl, 
and with a minor spiral regularly intercalated between the major spirals. 
Height of shell, 47; of last whorl, 37; of aperture, 27.5; breadth, 27 mm. 
(Dali.) 
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