AGRICULTURAL EXPERIMENT STATION. 113 



They were obtained from a neighbor, who had them from Ander- 

 son, of N. Y. I find that my neighbor's are also dying 

 with the same disease." Mr. H. H. Osgood, of Bluehill, reports 

 the same disease as affecting his bushes of Shaffer's Colossal rasp- 

 berry. 



History. This disease was first considered by Prof. Burrell 

 under the name "Raspberry Cane Rust," but it is now generally 

 known as AntJiracnose. It is a foreign species, but has become 

 widely distributed in this country and does much damage to rasp- 

 berries and blackberries. 



Characters. It attacks the canes, leaves, petioles of the leaves, 

 and in some cases the fruit. It attacks both the fruiting and 

 non-fruiting canes. It first appears near the base of the canes as 

 small, purplish spots. As the disease advances it encroaches 

 upon the tops, and in the last stages will attack the petioles, 

 leaves and fruit. The purplish spots enlarge and finally coalesce, 

 producing irregular, light-colored, blister like patches, often over 

 an inch long and sometimes encircling the stem, producing the 

 same effects as girdling with a knife. The leaves and fruit are 

 much dwarfed from a want of nourishment and finally the plants 

 die. The disease lives over winter upon the young canes attacked 

 and renews its ravages the next season. 



The fungus producing these effects is a microscopic, internal, 

 thread-like parasite, that creeps between the cells of the host 

 plants, sapping their vitality. It does not usually enter the pith, 

 but confines its ravages to the cells of the bark and cambium 

 layer, causing them to shrivel and die. Near the centre of the 

 diseased spots, where the ends of many of the capillary threads 

 of the fungus meet and unite, are formed masses of short, club- 

 shaped bodies called hasidia. These are formed under the 

 epidermis of the bark and finally burst it, appearing enveloped in 

 a globule of gelatinous matter. Upon the ends of these basidia 

 are borne singly, small, colorless, oblong, or oval celled bodies 

 called spores. The spores are the reproductive elements and serve 

 to spread the disease to adjoining plants and patches. The spores 

 are held together in the gelatinous matter, which is soluble in 

 water. The spores are liberated during rains and rapidly germin- 

 ate in drops of water on the plants. Dry weather prevents the 

 spread of the disease to new places, though the fungus will con- 

 tinue to grow in dry weather on canes where it is established. 

 Spores liberated by rains are in a condition to be blown by the 



