3<X) Journal of Agricultural Research vol. xx, No. 4 



The galls reach full development (PI. 54, B) early in the summer, in 

 early June in northern California. From this time on the majority of 

 them begin to decay if moisture is abundant, or to shrivel and dry 

 with the coming of drouth. However, in almost all fields a few galls 

 more deeply situated become covered with a corky layer and survive 

 the winter. 



When plants are subjected to dry conditions in late summer, as they 

 usually are in the Rogue River Valley in Oregon, many of the galls do 

 not decay but remain living throughout the autumn and winter. It 

 does not appear that such galls make appreciable growth during the 

 following year. Nevertheless, gall tissue may accumulate around old 

 plants in considerable mass. The exterior becomes covered with a 

 brown, corky layer that has a much warted appearance. This accumu- 

 lation of gall tissue has not been found on plants that have grown in 

 well-irrigated fields. 



At whatever age or state of development these galls are found, they 

 possess one distinctive character that is discovered when they are cut 

 open. The interior of the galls contains many small, irregularly shaped 

 brown masses of fungus spores which are easily visible (PI. 56, B). In 

 old dried galls the host tissue has shrunken so much that the spore 

 mass often occupies a large portion of the mass of the gall. Even in 

 decayed galls that have not yet been broken to fragments the spore 

 masses can be recognized by their golden brown color. 



CAUSAL ORGANISM 

 NOMENCLATURE 



Some difference of opinion concerning the identity of the parasite 

 causing crownwart of alfalfa has prevailed. Von Lagerheim (24) seems 

 first to have regarded it as a new and distinct species, which he cited 

 as Cladochytmim aljaljae. Later, however, he (14) identified it with 

 Urophlyctis (Physoderma) leproidea, a parasite causing conspicuous mal- 

 formations on the beet, originally described from Algeria by Trabut (34) 

 and assigned by him as well as by Saccardo and Mattirolo (26) to a 

 new Ustilaginous genus, Oedomyces. In making this disposition, von 

 Lagerheim opposed the views of both Vuillemin (55), who had identi- 

 fied Trabut's beet organism with Urophlyctis (Cladochytrium) pulposa 

 (Wallroth), long known to be parasitic on species of Chenopodium and 

 Atriplex, and of Magnus (18-20), who later came to regard the 

 parasites on Chenopodium spp., on the beet, and on alfalfa as three dis- 

 tinct species. None of these views appear to be based on evidence alto- 

 gether conclusive; nor can we adduce such evidence here, because the 

 lack of fresh diseased material of beet and of Chenopodium spp. have 

 made it impossible to attempt cross-inoculation experiments. 



