62 BOTANICAL GAZETTE [JANUARY 
The mesocarp is but a few cells thick, except at the margins. 
Scattered crystal-bearing cells occur either singly or in groups. 
The endocarp is made up of a single layer of thin-walled elon- 
gated cells. 
SPERMODERM.—The palisade cells are 30-50 uw in height and 
7p in diameter, with a narrow light line about 7» from the outer 
end. They differ from the palisade cells of alfalfa in that they are 
slightly higher, and from those of red clover in that they are rounded 
(not flattened) on the outer ends. 
The subepidermal cells are not distinguishable from those of 
alfalfa and red clover. 
The parenchyma consists of thin-walled collapsed cells. 
The ENDOSPERM and EMBRYO are of simple structure of no 
diagnostic importance. 
Identification in ground material 
In a coarsely ground product, fragments of the leaves, flowers, 
pods, and seeds may be picked out and identified, but when pow- 
dered the unicellular hairs and crystals are the most conspicuous 
Alfalfa Red clover Alsike clover 
Lower epidermis of | Wavy walls Deeply sinuous Straight walls 
nen Papa walls with pr 
jections at 
angles and about 
mata 
Unicellular hairs... .. Average diameter | Average diameter | Average diameter 
, warts 30 #, warts 13 #, warts indis- 
prominent prominent, aris- 
ing from epider- 
mal swelling 
elements. Red clover may be distinguished from alfalfa and 
alsike clover by its larger, stiffer, and more numerous unicellular 
hairs arising from a swelling of the epidermis; alsike clover, from 
alfalfa and red clover, by the less distinct warts on the unicellular 
hairs. 
The cell walls of the lower epidermis of the leaf are also char- 
acteristic, those of alsike clover being straight, of alfalfa simply 
