August e, 1909] 



SCIENCE 



185 



this country in 1857. A critical botanical, 

 agronomic and historical study of this strain 

 has been made by the writer during the past 

 three years. These observations indicate that 

 another explanation of the hardiness of this 

 alfalfa is at hand. Instead of its being pure 

 Medicago saliva, as has generally been sup- 

 posed, it appears to possess a small proportion 

 of Medicago falcata in its ancestry. M. fal- 

 cata is the hardy drought-resistant yellow 

 falcate podded alfalfa found wild in Eurasia. 

 Its hardiness and drought resistance are shown 

 by its natural growth on the dry cold steppes 

 of Siberia, far north of the range of M. 

 sativa. M. falcata differs from M. sativa in 

 its tendency to a decumbent growth, yellow 

 flowers instead of violet, falcate instead of 

 three-coiled pods, tendency to produce super- 

 numerary leaflets, greater resistance of the 

 leaves to frosts, and smaller seeds. The 

 hybrids between M. sativa and M. falcata 

 show a mass of varying but usually inter- 

 mediate forms. The flower color shows great 

 variation in the different hybrids and many of 

 the individual plants show a progressive color 

 change, passing from violet in the bud or 

 young flower through blue, green, greenish- 

 yellow, and some may reach an almost pure 

 yellow before the flower withers. This is a 

 somewhat unique form of inheritance in that 

 the flowers first show the influence of the M. 

 sativa parentage and later the influence of 

 the M. falcata ancestor. In all the characters, 

 as well as in the size of the different floral 

 parts, the Grimm alfalfa shows slight but defi- 

 nite departures from the corresponding char- 

 acters of M. sativa toward those of M. falcata. 

 Of the agronomic characters, the hardiness 

 and recently noted drought resistance are most 

 noteworthy. The slightly greater tendency of 

 the plants of the Grimm alfalfa to lodge does 

 not materially affect the usefulness of the 

 strain. The presence of variegated flowers 

 showing colors changing progressively from 

 violet to blue, green and sometimes approach- 

 ing and even reaching yellow, is perhaps the 

 most noticeable characteristic. While about 

 two thirds of the plants produce flowers of the 

 violet of ordinary alfalfa; in about one third 



other colors are shown in the flowers, many of 

 which show the progressive color changes as 

 indicated above. 



Similar studies have also been made of sev- 

 eral other strains which have proved them- 

 selves to be both very hardy and drought re- 

 sistant. So far as observed these have shown 

 the variegated flowers and other correlated 

 characters as noted for the Grimm alfalfa. 

 The most noteworthy example of this is the 

 commercial sand lucerne. This has proved 

 on trial to be much nearer ordinary alfalfa 

 than the botanical and agronomic literature 

 on the subject would indicate. The original 

 sand lucerne was apparently strictly inter- 

 mediate between M. sativa and M. falcata. 

 These forms are decidedly unstable and readily 

 cross with ordinary alfalfa, whether it be 

 grown in adjacent fields or from the seed 

 having been consciously or unconsciously 

 mixed. It has been found impossible to 

 secure the original form of sand lucerne on 

 the market and the commercial form is all 

 that appears to be obtainable. Experiments 

 by the writer indicate that the pollen of ordi- 

 nary aKalfa is prepotent over the pollen of 

 the hybrid plants' own pollen. The successive 

 intercrossing with ordinary alfalfa offers an 

 explanation for the close approach to ordinary 

 alfalfa, while still retaining many traces of 

 the M. falcata parents, especially the hardi- 

 ness and drought resistance. 



In advancing the influence of the M. falcata 

 as the primary explanation of the hardiness 

 of the Grimm alfalfa it was found that the 

 consensus of opinion among the old neighbors 

 of Mr. Grimm is that Grimm alfalfa has not 

 materially increased in hardiness since it was 

 introduced into this country. In the issue of 

 the Farm Stock and Home, Vol. 20, page 65, 

 the following statement is made: 



It [Grimm alfalfa] was grown successfully from 

 the start, but for many years not much attention 

 was paid to it and no great quantity was grown. 



In a circular entitled " Grimm's Everlasting 

 Alfalfa," published by Mr. A. B. Lyman, of 

 Excelsior, Minn., who first called attention to 

 the hardiness of this alfalfa, the author states 

 as follows : 



