red, shining,
flattened, kidney-shaped or ovoid, .4-.6 mm. long, concave on the
thinner edge from which protrudes a nipple-like point, a low central
ridge passing over the rounded edge. Native of warmer America. Needing
sand.

PINK FAMILY. CARYOPHYLLACEAE.

[Illustration: Fig. 61.]

=Cockle.= _Agrostemma Githago_ L. Flowers rose-colored; pod
erect, ovoid, about 16 mm. long; seeds dark brown to black,
wedge-shaped-triangular, appearing as though the two extremities were
bent together; surface covered with curved rows of conspicuous teeth,
one side 3-3.5 mm. long. Introduced from Europe. In no sense a weed
except in wheat fields.

[Illustration: Fig. 62.]

=Thyme-leaved Sandwort.= _Arenaria serpyllifolia_ L. Flowers white;
seeds reddish brown to lead color, slightly flattened, circular to
short-kidney-shaped. Each side covered with 4-5 curved rows of smooth,
oval tubercles, giving the appearance of having two extremities bent
together, about 5 mm. in diameter. Naturalized from Europe, delighting
in light, poor soil. When well grown it becomes a tumbleweed.

[Illustration: Fig. 63.]

=Larger Mouse-ear Chickweed.= _Cerastium vulgatum_ L. Flowers white;
pods cylindrical; seeds light-reddish yellow to dark reddish brown;
slightly flattened, 4-sided, 2 of them straight, converging, one
rounded, the other narrow and notched. Some of them ovoid, others nearly
circular, covered with a few irregularly curved rows of tubercles, .4-.8
mm. in diameter. In large part introduced from Europe, though a native
of this continent.

[Illustration: Fig. 64.]

=Bouncing Bet. Soapwort.= _Saponaria officinalis_ L. Flowers white;
seeds dark lead-color, flattened, short-kidney-shaped to circular with
notch on one side, 2 mm. across, more or less, with 6-7 curved rows of
short, shiny tubercles. Naturalized from Europe, delighting in sandy
soil.

[Illustration: Fig. 65.]

=Cow-herb.= _Saponaria Vaccaria_ L. Seed dull, jet-black, slightly
roughened by great numbers of minute points, nearly spherical, 2.3 mm.
in diameter. An annual very troublesome in spring wheat. Introduced from
Europe.

[Illustration: Fig. 66.]

=Sleepy Catch-Fly.= _Silene antirrhina_ L. Flowers pink; seeds
lead-color, slightly flattened, circular to short-kidney-shaped, each
side covered with 5-6 curved rows of pointed tubercles giving the
appearance of having two blunt extremities bent together, .5-.7 mm.
across. Compare seeds with those of _Arenaria_ above