62 Journal of Agricultural Research voi. xii, no. » 



Tables VII to XII show the cultural characters on the lo agars for 

 Fomes rimosus (two strains) from Acacia roemeriana (catclaw), F. 

 rimosus from Siderocarpos flexicaulis (Texas ebony), F. rimosus from 

 Prosopis juli flora (mesquite), F. robiniae from Robinia neomexicana and 

 a species of Fomes from Juglans rupestris (?). A study of these six 

 tables fails to show any marked and constant differences in cultural 

 characters for any of the lo agars for the six strains given, although four 

 of the six strains represent Fomes rimosus, one F. robiniae and one a 

 Fomes on Juglans rupestris ( ?) which the writers have been referring to 

 F. everhartii. Some of the cultures on carrot, malt, and parsnip show 

 slight color differences, but none great enough to be of any specific value. 

 On parsnip and malt, the submerged mycelium for all of these strains is 

 colored, while carrot has colored to colorless mycelium. The dominant 

 characteristics of Fomes rimosus is seen on beet, celery, bean, and alfalfa 

 agars. On each of these agars there is but little really aerial mycelium 

 which is downy to mainly appressed, while the submerged mycelium 

 extends far beyond the aerial mycelium, giving a peculiar and very 

 characteristic glassy appearance to the surface of the agar. This peculi- 

 arity of growth of the submerged mycelium on these four agars is seen 

 in all of the six strains and indicates that they are one and the same 

 species — viz, that Fomes robiniae is only a form of F. rimosus, as many 

 scientists have always believed, and that the specimen of Fomes sp. 

 supposed to have been collected on Juglans rupestris also belongs to this 

 species. These six examples show how valuable the cultural characters 

 can become in determining the specific position of closely related or 

 identical species. Only one viable sporophore of the Fomes supposed to 

 have been collected on /. rupestris was available for culture work, and 

 since this specimen may have been wrongly labeled as to host, the 

 writers do not wish to place the Fomes so common on /. rupestris through- 

 out the southwestern United States as belonging positively to Fomes 

 rimosus until further cultures with specimens absolutely known to have 

 grown on this host have been made. 



The cultural characters of Fomes everhartii, F. arctostaphyli (lo), F. 

 igniarius from Populus tremuloides, and a species of Fomes from Alnus 

 sp., sent to the writers as F. igniarius, when compared showed that the 

 Foines from Alnus is more closely related to F. arstostaphyli than to 

 F. igniarius from P. tremuloides, but that it is apparently neither of 

 these two species; nor did it have any of the cultural characters of F. 

 everhartii. In this instance the sporophore from Alnus sp. was very 

 similar in all its characters to the sporophore of F. igniarius from P. 

 tremuloides, yet the cultural characters instantly showed the two were 

 not the same species. 



Polyporus farlowii, P. dryophilus, and P. texanus are three closely 

 related species which differ but little in their general sporophore charac- 

 ters. Tables V, VI, XIII, and XIV show the cultural characters of each 



