220 ANNUAL REPORT. 



been carried and have germinated. Many fungi of this class produce 

 their winter spores on fallen leaves or twigs, for instance the black 

 blotch fungus of maple leaves. 



It is probable that this currant fungus has some winter form on the 

 dead vegetable matter about the bushes. Hence the remedy should be 

 sought in burning the leaves that fall and any other rubbish that might 

 harbor the fungus. 



A similar species Septoria rubi, West, is very common on blackber- 

 ries all over the country. It produces roundish spots with a red or 

 purple margin and a brown center. 



DOUBLE BLOSSOM. 



"Double blossom" is the name given to a blackberry disease that is 

 quite prevalent and destructive in some regions. It is a disease of the 

 blossoms, as the name implies, but they are not actually double. The 

 several parts are abnormally swollen through the eflPect of the fungus, 

 so that at a casual glance the flower appears double. It is killed of 

 course and no fruit is formed. The mycelium runs through the 

 tissue of the floral organs, swelling and distorting them, and at length 

 sends out on the surface clusters of short, colorless threads, which bear 

 the spores on their ends and produce a whitish, mealy appearance over 

 the flower. The spores are slender and pointed, frequently curved, 

 and divided by cross-partitions into two to four cells. 



This disease was first observed and studied by 

 Mr. F. S. Earle. He sent specimens to Dr. Win- 

 ter of Germany and the latter has recently des- 

 cribed and published it as a new species, which 

 he refers with doubt to the genus Fusisporium figure e-spores of double 



, . _, . . blossom fungus, /u«iisporJu?ii 



and calls If USlSporiUm rilbl. rubi, on blackberry. (After 



Earle.) 



RASPBERRY CANE RUST. 



The cane rust of raspberries and blackberries is rather inconspicuous 

 but very destructive. It was first studied by Professor T. J. Burrill, 

 who published an excellent account of it in the Agricultural Review 

 for November, 1882. He states that it was first observed in 1878; since 

 that time it has spread rapidly and caused great damage. One instance 

 is given of a blackberry field that yielded a profit of four hundred dol- 

 lars a year with promise of increase. This disease reduced it so that it 

 scarcely paid expenses the next year. 



The spots on the canes are rounded, of a grayish color and surround- 



