26 



BULLETIISr 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 Medicago 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- 



