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SEMELIDAE 435
Semele pwpiirascens Gmelin Purplish Semele
North Carolina to south half of Florida and the West Indies.
Plate 40b
I to i^ inches in length, oblong, thin-shelled, smooth except for very
fine concentric growth threads over which run another set of fine, microscopic
concentric lines at an oblique angle. External color variable: commonly
gray or cream with purple or orangish mottlings. Interior glossy and
suffused with purple, brownish or orange. A fairly common, shallow-water
species.
Semele bellastriata Conrad Cancellate Semele
North Carolina to south half of Florida and the West Indies.
Plate 30)
/4 to % inch in length, similar in shape to piirpurascens, but a much
smaller species with numerous radial and concentric riblets which cross to
give a cancellate appearance. Some specimens well-beaded, others have the
radial ribs more prominent. External color yellowish white with reddish
flecks or a solid, purplish gray. Interior white, cream or suffused with mauve
or violet, 5. cancellata Orbigny is this species. Fairly common just offshore.
Semele nibropicta Dall Rose Petal Semele
Alaska to Mexico.
Plate 29\v
I to 1% inches in length; beaks % toward the posterior end; rather
thick-shelled, especially in the south. Concentric sculpture of small, irreg-
ular growth lines. Radial incised lines numerous. Periostracum thin, smooth
and yellowish brown. Exterior of shell dull grayish or tannish white with
faint, radial rays of light-mauve. Imterior glossy-white, with a small splotch
of mauve at both ends of the hinge line. Uncommon from 20 to 50 fathoms.
Se77iele rupicola Dall Rock-dwelling Semele
Santa Cruz, California, to the Gulf of California.
Plate 29t
I to 1% inches in length. Irregular in shape: ovalish, oval-elongate or
obliquely oval. Exterior yellowish cream with numerous, concentric crinkles
and a few ^eak radial threads. Interior glossy, white at the center, bright
purplish red at the margins and hinge. John Q. Burch finds this species common
in Chama and Mytilus beds and in rocks and crevices.
Semele decisa Conrad Bark Semele
San Pedro, California, to Lower California.
Plate 29Z