Page:American Seashells (1954).djvu/124

106 $3/4$ to 1 inch in maximum diameter, usually very flat, rather thin, oval in outline but narrower at the anterior end. Neatly sculptured with numerous radial threads. Color variable: exterior whitish with a few or many narrow or wide radial rays of brownish green. Interior glossy whitish with a dark- or light-brown callus. Borders or sometimes the entire inside marked by numerous radial lines of purple-brown. These are often divided near the edge of the shell. Uncommon in Florida, but abundant in the West Indies. A. candeana Orbigny and A. tenera C. B. Adams are the same.

1 inch in maximum diameter, oval in outline, moderately flat with rounded sides. Shell thick, with coarse axial ribs which are crossed by ﬁne concentric threads. Interior glossy-white, with the central callus yellowish. Exterior chalk-white, dull. Sometimes flecked with red-brown dots and bars. Common. Formerly known as punctulata Gmelin. A deep-water form, which is perhaps a young phase, of this species is very thin, light-rose in color, with a tiny, sharp apex and is occasionally flecked with red. It may be called A. pustulata pulcherrima Guilding.

$1/3$ to $1/2$ inch in maximum diameter, high-conic, with numerous, alternating black and white rays. The black rays divide into two near the edge of the shell. Radial riblets weak, usually black. Interior white, often stained brown or black on the callus. Frequently found adhering to the underside of large gastropods such as Livona pica. Common. A. cubensis Reeve and A. simplex Pilsbry are probably this species.

$1/2$ inch in maximum diameter, moderately high, with roundish sides, thick, with about 15 to 20 rather large, rounded, white radial ribs on a black-brown background. Sometimes completely white. Interior white, occasion-