nalis_ (L.) Scop.
_Panicum sanguinale L. Syntherisma_ (L.) Nash. Spikelets before severe
rubbing, oblong, acute, 2.5-3.5 mm. long, first glume on flattened side
minute, second on rounded side about half as long as the spikelet,
pubescent or nearly smooth, third glume more or less pubescent,
5-7-nerved; floret, after severe rubbing, smooth, edges of floral glume
thin. Introduced from Europe. Roots very tough and coming from the lower
joints.

[Illustration: Fig. 13.]

=Barnyard Grass.= _Echinochloa Crus-galli_ (L.) Beauv. _Panicum
Crus-galli_ L. Florets oval, white, yellowish gray or brown, 2.4-3 mm.
long, plano-convex, glume on the convex side, highly polished, three
obscure longitudinal nerves. Native of this country.

[Illustration: Fig. 14.]

=Yard-Grass. Wire-Grass.= _Eleusine Indica_ (L.) Gaertn. Florets light
lead color or brown before threshing or much rubbing; grain dark,
reddish brown, 1.2-1.4 mm., ovoid with the base abruptly pointed, 3
sided, the corners rounded, a vertical groove along one side; seen from
the back with the groove side down and base toward the observer,
starting from an oval spot near the base, 10-15 ridges on each side,
extend downward and forward. Introduced from some warmer region of the
Old World.

[Illustration: Fig. 15.]

=Stink-Grass.= _Eragrostis megastachya_ (Koeler) Link. _Eragrostis
major_ Host. Grain orange red or wine color .4-.6 mm. long. Broad oval
to nearly circular, very slightly flattened, extremities slightly
pointed, embryo within one edge near the base, a fine network of dark
lines evident under a good lens. Introduced from Europe.

[Illustration: Fig. 16.]

=Squirrel-tail Grass.= _Hordeum jubatum_ L. Spikelets in clusters of
three, central one only fertile, 5 mm. long, containing a grain adhering
to the floral glume and palea, the other two abortive, seven awns in
these three spikelets, 4-6 cm. long, four others less than 1 cm. long;
awns and fragment of rachis holding the cluster of spikelets together,
all barbed upward, making them troublesome for fleeces of sheep and the
mouths of animals eating them. Native of this country and widely
distributed.

[Illustration: Fig. 17.]

=Old Witch Grass. Tickle Grass. A Tumble-Weed.= _Panicum capillare_ L.
Florets flattened, elliptical, apex abruptly pointed, about 1.5 mm.
long, highly polished, leaden gray, lighter at the extremities and along
the edges of the glume, five slender light colored nerves join the
extre