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tive blue and white enamel signs bearing the words, Brooklyn 

 Botanic Garden, with an arrow underneath pointing to the proper 

 exit to reach the Garden. This exit is within about 50 feet of our 

 Eastern Parkway entrance. The cost of the signs was met from 

 Botanic Garden private funds. 



Similar signs were placed in the Prospect Park Station of the 

 Brooklyn Rapid Transit Subway (Broadway Subway) without 

 expense to the Garden. 



Investigations 



Plant Pathology 



The investigations in Plant Pathology have been continued by 

 Dr. Reed and collaborators along the general lines described in the 

 last Annual Report of the director. 



Dr. Reed's experiments on the varietal resistance of sorghums 

 to the covered kernel smut (Sphacelotheca Sorghi (Link) Clint.) 

 have been continued. A series of experiments with the loose 

 kernel smut (Sphacelotheca crucnta (Kuhn) Potter) was also 

 carried out and a careful comparison of the behavior of a large 

 number of varieties of Sorghum to these two smuts was made. 

 In general, the different varieties responded in the same fashion 

 to the two smuts. Certain varieties, as the Milos and Feterita, 

 showed a marked resistance to both. The Kafirs, Sorgos and 

 Durras proved to be quite susceptible to both smuts. Some of the 

 Kaoliangs proved susceptible but Dwarf Brown Kaoliang proved 

 highly resistant to both smuts. Darso has consistently proved 

 highly resistant to the covered kernel smut; on the other hand, 

 it was readily infected by the loose kernel smut. Darso was the 

 only striking case of a marked difference in the behavior of a 

 sorghum towards the two smuts. 



Very interesting results were also obtained bearing upon the 

 influence of soil temperature and soil moisture on infection by 

 covered kernel smut of Sorghum. These experiments will be 

 repeated and extended during the present season before reaching 

 a final conclusion as to the influence of these various factors. 



In connection with the oat smuts, Ustilago avenae (Pers.) Jens, 

 and U. levis (K. & S.) Magn., a few varieties were again tested. 

 For the most part, these varieties were those which had shown 



