CLASS GASTROPODA 145 
adductors rounded and broader than the rest, connected by a slender 
impressed line marking the attachment of the mantle. Young shells are 
often furnished with irregular riblets more or less strong, many or few 
in number, radiating from the apex, but stronger toward the margin. 
Color dead-white inside and out, often livid or tinged a fine pink or pea- 
green from Nulliporc, never wax-yellow or horny-pellucid as in the normal 
state of Sc arris scurra . Length, 35 ; breadth, 31; alt., 23 mm. (Tryon and 
Pilsbry, Manual of Conchology .) 
Type in St. Petersburg? Type locality, Bering Sea. 
Range. Pribilof Islands, Bering Sea, to San Diego, California. 
Acmaea mitra funiculata Carpenter, 1864 
Supplementary Report, British Association for the Advancement of Science, 650. 
Shell small, whitish, regularly conical, apex acute, elevated, a little in 
front of the middle; sculptured with strong rounded riblets, sometimes a 
little nodulous; sometimes single, sometimes gathered into two's and 
three’s; with wide interspaces in which intercalary riblets appear. Length, 
6; breadth, 4*4 ; alt., 3 mm. (Tryon and Pilsbry, Manual of Conchology.) 
The measurements are from the type. 
Type in United States National Museum. Type locality, Monterey, 
California. 
Range. Shumagin Islands, Alaska, to Magdalena Bay, Lower Cali¬ 
fornia. 
SECTION COLLI SELLA Dali, 1871 
Acmaea cassis Eschscholtz, 1833 
Plate 94, figs. 5, 6 
Zoological Atlas, 19: PI. 24, fig. 3. 
Testa ovato-oblongata, elevata intus alba, extus rutilo-fusca, costis latis 
rotundatis fornicatis inaequalibus, vertice excentrico, erecto obtuso, mar- 
gine repando. (Eschscholtz.) 
Die aussere Flache ist, wie auch gewohnlich bei fast alien folgenden 
Arten, etwas rauh anzufuhlen, und hat das Aussehen, als sei eine Deck- 
farbe in einer ziemlich dicken Schicht auf die Schale aufgetragen. Die 
Rippen entspringen ziemlich tief unterhalb des Gipfels, werden gegen den 
Rand Schale immer breiter, sind an Lange und Dicke unter einander etwas 
ungleich und erscheinen als Falten der Schale, so dass also der Konvexitat, 
die jede nach aussen zeigt, inwendig eine Konkavitat entspricht. Lange, 1 
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