60 BOTANICAL GAZETTE [JANUARY 
similar to those on the leaves and stem. The bristles, with papillae 
the whole length, end with a tuft of stiff unicellular hairs. 
Mesophyll.—A single layer of crystal-bearing cells is conspicuous. 
The inner epidermis is made up of wavy-walled cells and occa- 
sional hairs. 
Corotta.—The epidermal cells have very thin walls with papil- 
lae and striated cuticle toward the tip. 
PERICARP.—The epicarp consists of sinuous-walled cells with 
scattered stomata. On the stem end the cell walls are thin, chan- 
ging abruptly toward the tip to greatly sae sclerenchyma- 
tized and pitted walls. 
The mesocarp cells are inconspicuous, with the exception of 
occasional scattered crystal-bearing cells. 
SPERMODERM.—The palisade cells average 45 uw in height (run- 
ning up to 55m over the radicle) and 7 uw in breadth. A narrow 
light line lies about 7 » below the thin cuticle. They differ from 
the corresponding cells of alfalfa in that they are higher and the 
outer ends are flattened. 
The subepidermal cells vary in height, but average 10 p. They 
are upward of 20 uv broad and constricted in the center with lower 
ends broader than outer. 
The parenchyma consists of thin-walled collapsed cells. 
€ ENDOSPERM and EMBRYO are of simple structure of no 
diagnostic importance. 
Alsike clover 
Alsike clover (Trifolium hybridum L.), although indigenous to 
Europe, has become very common in America. The plant branches, 
with erect stems bearing 3-foliate toothed leaves on long petioles 
and pedicellate flowers forming a loose round head on a long 
peduncle. Like alfalfa, the plant is described as smooth, though 
hairs are evident under a lens and are of diagnostic importance with 
higher magnifications. The membranous 5-cleft calyx is much 
shorter than the delicate rose-pink tubular corolla, which after 
flowering becomes brown and withering-persistent. The pod 
differs from that of alfalfa in that it is straight and from red clover 
in that it is 2-4-seeded. The greenish brown seeds are smaller 
