296 Journal of Agricultural Research vol. xx, no. 4 



more desirable than formerly that the disease caused by Urophlyctis 

 should have a distinctive name. The fact that the name crownwart is 

 well established in usage is much in its favor. It will be seen, however, 

 from facts presented later in this paper that this name is somewhat 

 misleading, inasmuch as the galls are not typical warty growths, nor are 

 they formed from the tissue of the so-called crown of the plant in a manner 

 comparable with that in which crowngalls are formed. A name more 

 truly distinctive is suggested by the French name used by Arnaud (j), 1 

 "La Maladie des tumeurs marbrees de la Luzerne." An English equiv- 

 alent, marbled gall of alfalfa, the word marbled referring to the mot- 

 tled effect produced by the brown spore masses seen when any of these 

 galls are cut, would call attention to the one distinctive character of 

 these galls observable at any time and would be accurately descriptive. 



HOST PLANTS 



Of the many species of the genus Medicago introduced into the United 

 States, Medicago sativa is the only one on which the disease has been 

 found commonly. McKee (77) found it also on M. falcata. The two 

 species, grown near together at the Plant Introduction Field Station at 

 Chico, Calif., seemed to be about equally infected. 



Spegazzini (32) records the fungus as occurring on Medicago denticulata 

 and species of Adesmia in Argentina. Hauman-Merck (11) also records 

 the fungus on M. denticulata from the same locality and further states 

 that it does not occur upon alfalfa. In view of the fact that search has 

 not revealed the fungus upon M. denticulata in the United States even 

 when the plant is growing abundantly close in association with diseased 

 alfalfa, it seems advisable to hold it an open question whether the fungus 

 found in Argentina upon M. denticulata and Adesmia spp. is identical 

 with that which causes the disease of alfalfa. 2 Thus, the evidence at hand, 

 while it is inadequate for the formation of final conclusions, appears to 

 indicate that the species of Urophlyctis occurring on M. sativa is prob- 

 ably limited to that species and to M. falcata. 



DISTRIBUTION AND ECONOMIC IMPORTANCE 



The only available information regarding the economic importance of 

 the disease consists of expressions of opinion based on a larger or smaller 

 amount of field observation. The trend of the opinion that has devel- 

 oped from this observation is that the disease is, or becomes locally, very 

 destructive to alfalfa plants. 



The first report of the disease by von Lagerheim (14) from Ecuador 

 gave inception to this trend. He states that diseased plants can easily 



1 Reference is made by number (italic) to " Literature cited," pp. 321-323. 



2 A portion of a collection of Urophlyctis alfalfae var. adesmiae on Adesmia bicolor, sent by Spegazzini to 

 the Office of Pathological Collections, Bureau of Plant Industry, has been examined and been found to 

 contain a Synchitrium rather than a Urophlyctis. 



