Plate 20
PACIFIC COAST UNIVALVES
a. ERODED PERIWINKLE, Littorina planaxis Phil., ^ inch (Washington to Lower California), p. 134.
b. SITKA PERIWINKLE, Littorina sitkana Phil., % inch (Alaska to Washington), p. 134.
c. CHECKERED PERIWINKLE, Littorina scutulata Old., Yj inch (Alaska to Mexico), p. 134.
d. FLAT WORM-SHELL, Spiroglyphus lituellus Morch (Alaska to California), p. 144.
e. SCALED WORM-SHELL, Aletes squami- geriis Cpr. (Alaska to Peru), p. 144.
f. ONYX SLIPPER-SHELL, Crepidula ojiyx Shy., 2 inches. Left shell lived on scallop (California to Chili), p. 171.
g. COOPER'S TURRET-SHELL, Turritella cooperi Cpr., 2 inches (California to Mexico), p. 141.
h. MARIA'S TURRET-SHELL, Turritella mariana Dall, 2^ inches (California to Panama), p. 142.
i. RECLUZ'S MOON-SHELL, Polinices reclii- sianus Desh., 2 inches (California to Lower California), p. 187.
j. WROBLEWSKI'S WENTLETRAP, Opalia wrobleivshii Morch, 1 inch (Alaska to San Diego, California), p. 162.
k. PACIFIC HALF-SLIPPER SHELL, Crepi- patella lingulata Gld., % inch (Alaska to Panama), p. 170.
1. PACIFIC CHINESE HAT, Calyptraea fastigata Gld., 1 inch (Alaska to Cali- fornia), p. 169.
m. GOULD'S DOVE-SHELL, Nitidella goiildi Cpr., Yi inch (Alaska to California), p. 222.
n. PACIFIC MUD NASSA, Nassarius tegula Reeve, % inch (California to Lower California), p. 238.
o. APPLE SEED, Erato vitellina Hinds, Yi inch (California to Lower California), p. 176.
p. IDA'S MITER, Mitra idae Melville, 2 inches (California), p. 249.
q. BEATIC DWARF OLIVE, OUveUa beatica Cpr., Y inch (Alaska to California), p. 247.
r. CALIFORNIAN FROG-SHELL, Bursa californica Hinds, 4 inches, with cluster of eggs laid on clam shell (California to Lower California), p. 199.
s. GIANT WESTERN NASSA, Nassarius fossatus Gould, 2 inches (Vancouver, B. C, to Lower California), p. 240.
t. Top view of living animal of Oliva, p. 245.
u. SOLANDER'S TRIVIA, Trixna solandri Sby., % inch (Catalina Island, Cali- fornia to Panama), p. 179.
v. CALIFORNIAN TRIVIA, Trivia californiana Gray, '2 inch (California to Mexico), p. 179.
w. X-ray photo of SPINDLE SHELL, Fusinus, p. 243.
