236 Report of the Department of Botany of the 



sionally. I do not believe that the teliospores ever have any part 

 in carrying the infection from currant over winter to the currant 

 again. 



'While this study, as we have conducted it, has been negative 

 and shows quite clearly that under usual circumstances the rust is 

 not propagated from year to year by the telia or uredinia, yet it 

 does not preclude the possibility of the rust passing by means of 

 the urediniospores from the currant to the currant again in the fol- 

 lowing season under certain favorable conditions. It does show, 

 I think, that the rust, at least most strains of it, are not likely to 

 persist long unless with the intervention of the white pine." 



Dr. Spaulding reports as follows: 



" The 200 Ribes nigrum bushes were received early in the winter. 

 They were promptly heeled in and held thus until February 1st. 

 On this date they were transferred to the experimental greenhouse. 

 They started off new growth promptly and very vigorously, a very 

 fine growth being obtained. Careful examinations were made of 

 these bushes several different times to determine whether the fungus 

 might be present upon them. The last examination was made 

 about the middle of May. None of the disease was found at any 

 time upon any of these bushes. About April 1st, I separated a 

 few of the plants from the rest and inoculated them with teleutospore 

 material received from you at that time. There were absolutely 

 no results from these inoculations. 



" In considering the results, it must be remembered that they are 

 entirely negative and are subject to the same limitations as are 

 any negative results. In my opinion, these results show that the 

 disease is not often carried over upon dormant Ribes stock. I do 

 not believe, however, the present series of experiments can be con- 

 sidered to have definitely shown that the fungus may not once in a 

 great while thus be carried over; that is, there is still left the pos- 

 sibility of this occurring once in a large number of cases." 



Dr. Clinton makes the following report on his experiments: 



" Late in the fall of 1912 I received from Stewart of the Geneva 

 (New York) Station, a number of black currants that had been badly 

 infected with the pine-currant rust. These were heeled in out-of- 

 doors, and left there until the last of February when twenty-nine 



