262 DOMESTICATED ANIMALS AND PLANTS 
Though this newest of our crops did not come into our own 
agriculture until approximately the opening of the twentieth 
century, it is, after all, the oldest and most anciently known of all 
our leguminous forage plants, excepting only the cowpea and 
soy bean, which are used mainly for their seeds. Alfalfa was 
known to the Greeks and Persians, who called it medica because 
it had been brought from Media at the time of the Persian War 
(470 B.C.), though it apparently did not come into general culti- 
vation until the first or second century after Christ. 
Candolle! has no hesitation in affirming that alfalfa is wild 
in several provinces to the south of the Caucasus, in various 
parts of Persia, in Afghanistan, Beluchistan, and Kashmir. Its 
seeming nonintroduction into China and India is a mystery, 
explainable only on the theory that the people preferred the 
plants that bore heavy seeds, or that they neglected it for 
some unknown reason akin to that which evidently deterred the 
Aryans from developing cultivated meadows. 
The student will not fail to be impressed with the remarkable 
significance of the fact that this oldest of all the cultivated for- 
age plants should have been the last to be introduced into our 
own agriculture, nor will he fail to note the scientific basis for 
the failure of our first attempts, which, had they been successful, 
might have greatly influenced the development of the eastern 
and the middle states. 
The lentil. This plant is evidently a puzzle to the botanists, 
by whom it is variously designated as Eris lens, Lens esculenta, 
and sometimes it is put in the genus Cicer. This confusion is 
probably due in part to the fact that the plant has been long 
cultivated. It has already been remarked that man, when main- 
taining himself with a small amount of animal food, quickly 
turns to seeds of legumes as a source of nitrogen. 
or only closely related is not yet known, but the student should understand 
that the sweet clover, though classified as a distinct species and in a different 
genus, is after all, in many respects, almost indistinguishable from alfalfa, es- 
pecially in its earlier stages of growth. 
1“ Origin of Cultivated Plants,” p. 103. 
