26 BULLETIN 428, U. S. DEPARTMENT OF AGRICULTURE. 
cago sativa. In the latter instance the names were applied in many 
cases without knowledge of the hybrid nature of the plants. There 
is very little justification for the attempts that have been made to 
describe and name forms of true I/edicago falcata, since the char- 
acteristics of these forms to which names have been applied are 
neither definite nor consistently correlated with other important 
characters. There would appear to be no justification for the at- 
tempts to name and describe unstable hybrids. Tournefort (60) was 
the first to do this, but he was not aware that the forms with which 
he dealt were hybrids. More recent botanists likewise have ap- 
parently failed to appreciate this fact with regard to material com- 
Fig. 13.—Individual plant of Medicago falcata, S. P. I. No. 24455, a medium broad 
crowned plant of ascending habit of growth, representing Group III. 
ing under their observation, as otherwise they doubtless would have 
refrained from describing hybrids as species or varieties. 
It has been possible to find among the department’s introductions 
and selections forms that answer to the description of most of the 
varieties of Medicago falcata and Medicago sativa that have been 
proposed by botanists. That many of these forms are hybrids is 
quite clearly indicated by the fact that their progeny even from 
one generation of self-fertilized seed breaks up in a manner charac- 
teristic of hybrids. Furthermore, certain of the so-called varieties 
have been created as a result of artificial crossing, and there is 
abundant reason to believe that a great many of them can be origi- 
