Plate 18
PACIFIC COAST UNIVALVES
a. KEYHOLE LIMPET, Megathura crenu- lata Sby., 4 inches (Monterey, Califor- nia, south), p. 99.
b. ROUGH KEYHOLE LIMPET, Diodora aspera Esch., 2 inches (Alaska to Lower California), p. 97.
c. VOLCANO SHELL, Fissurella volcano Reeve, 1 inch (Crescent City, California, south), p. 100.
d. TWO-SPOTTED KEYHOLE LIMPET, Megatebennus hiniacidatus Dall, '^2 inch (entire coast), p. 99.
e. HARD-EDGED KEYHOLE LIMPET, Liicapiriella callomargijiata Dall, 1 inch (California, south), p. 99.
f. FINGERED LIMPET, Acmaea digitalis Esch., 1 inch (Alaska to Mexico), p. 103.
g. TEST'S LIMPET, Acmaea conus Test, % inch (California to Lower California), p. 102.
h. WESTERN BANDED TEGULA, Tegula ligidata Menkc, % inch (Monterey, California, south), p. 120.
i. CARPENTER'S DWARF TURBAN, Ho- malopoma carpenteri Pils., ^/;j inch (entire coast), p. 126.
j. GIANT OWL SHELL, Lottia gigantea Gray, 3 inches (Crescent City, Califor- nia, south), p. 101.
k. GILDED TEGULA, Tegula anreotincta Forbes, 1 inch (Southern California, south), p. 120.
1. ROUGH LIMPET, Acmaea scabra Gould, 1 inch (Washington to Lower Califor- nia), p. 103.
m. NORRIS SHELL, Norrisia norrisi Sby., V/j inches (Monterey, California, south), p. 117.
n. SHIELD LIMPET, Acmaea pelta Esch., 13^2 inches (Alaska to Lower California), p. 102.
o. FILE LIMPET, Acmaea limatula Cpr., 1 V^ inches (Northern California, south), p. 102.
p. WAVY TURBAN, Astraea nndosa Wood, 3 inches (Ventura, California, south), p. 124.
q. MASK LIMPET, Acmaea persona Esch., Ij,^ inches (Alaska to Monterey, California), p. 103.
r. WHITE CAP LIMPET, Acmaea mitra Esch., 1 inch (Alaska to off Lower Cali- fornia), p. 101.
s. GRANULOSE TOP-SHELL, Calliostoma snpragranosum Cpr., 3^2 inch (Monterey California, south), p. 115.
t. FENESTRATE LIMPET, Acmaea fenestrata Reeve, 1 inch (California, south), p. 102.
u. CALIFORNIAN LIOTIA, Liotia fenestrata Cpr., % inch (Monterey, California, south), p. 122.
v. SPECKLED TEGULA, Tegula gallina Forbes, 1 inch (San Francisco, Califor- nia, south), p. 119.
w. CRIBRARIA LIMPET, Acmaea fenestrata cribraria Gould, 1 inch (Alaska to Ca- lifornia), p. 102.
x. MONTEREY TEGULA, Tegula moulereyi Kiener, Ij^ inches (California), p. 121.
y. DUSKY TEGULA, Tegula pulligo Gmelin, 1 inch (Alaska to California), p. 120.
z. SEAWEED LIMPET. Ac7naea insessa Hinds, ^4 inch (Alaska to Lower Cali- fornia), p. 105.
z.z. UNSTABLE LIMPET, Acmaea insiabilis Gould, 1 inch (Alaska to San Diego, California), p. 105.