Arthur: Uredinales of Costa Rica 



115 



specimens Hemileia vastatrix, which are affected with ' maya,' a 

 very common disease in San Jose. To my knowledge Hemileia 

 vastatrix* has not at any time invaded the American continent, its 

 dependencies, or the West Indies." 



Mr. Cox in his letter of May 12, 1916, says : ' k Evidently some- 

 one, not Tonduz, has blundered, and knowing by hearsay of 

 Hemileia vastatrix as a coffee-leaf disease, has assumed that 

 Tonduz' specimen leaves of a coffee-leaf disease were affected 

 by the disease he or she had read about, i. e., H. vastatrix. 

 I personally have never seen or heard of H. vastatrix in Costa 

 Rica, nor known of anyone else who has, and e there is not the 

 slightest difficulty in recognizing it." 



The coffee-leaf rust, H. vastatrix, doubtless does not occur in 

 the western hemisphere at the present time. It was first ad- 

 mitted to the North American flora on the strength of a state- 

 ment that it was once found in Porto Rico. It certainly does 

 not exist there now, whatever truth may have been in the report, 

 and has not recently been heard of from any other locality in 

 either North or South America, or in the adjacent islands. The 

 entries in the North American Flora (7:150. 1907), and in 

 Sydow's Monographia Uredinearum (3:210. 1914), should be 

 cancelled. 



When the possibility was being considered that the coffee rust 

 did occur in Central America, Professor Holway wrote under 

 date of March 2, 1916, as follows: " The first two collections of 

 the Inga rust [which I made in Costa Rica] were on young 

 plants, four feet high, growing with coffee plants, one growing 

 from the same spot as a coffee tree. The likeness in young speci- 

 mens is remarkable — several natives saying at once that the Inga 

 was coffee. Fresh, young shoots are practically identical. The 

 importance of the rust prevented my being caught. I first found 

 the taste quite different and later discovered a larger tree of Inga, 

 in which the close resemblance disappears. It is evident that 

 future reports of the occurrence of the coffee rust, not founded 

 upon examination of the fungus, must be taken with caution." 



This first presentation of 118 species of rusts for Costa Rica, 

 here given, including 22 species new to science and 12 previously 



