BACTERIA 517 



oleae, Trev.). The disease occurs throughout the Medi- 

 terranean region wherever the olive is grown, and it is also 

 present in California. So far as is at present known the 

 organism can only effect an entrance into the plant through 

 wounds. When a nodule is once produced, it has been 

 proved that the bacteria may migrate to some distance by 

 way of the vascular system, and form other tubercles which 

 thus originate from within the host. These tubercles finally 

 rupture the epidermis and form nodules. 



The organism consists of cylindrical rods with rounded 

 ends, singly or in short chains, 1-2-3 X 0-4-0-8 l x - The 

 organism is motile, having 1-4 polar flagellae. 



Rich soil, too much manure, and too much water favour 

 the disease. Pruning all diseased branches checks the 

 disease, but it is important that a knife used for removing 

 diseased branches or cutting out tubercles should be sterilised 

 before it is used on healthy parts. Large tubercles should 

 have a portion of the underlying wood also removed, and 

 the wound should be at once sterilised and protected. 



Pierce, Journ. My col., 6, p. 148. 



Savastano, Ann. R. Scuola Sup. d' Agric. in Portici, 5, 

 fasc. 5 (1887). 



Smith, E. W., U.S. Dept. Agric, Bureau of Plant Industry, 

 Bull. No. 131, pt. 4 (1908). 



Voglino, I Fungi Dannosi alle, Piante Coltivate. 



Calla lily rot. Dr. Townsend has described a soft rot 

 of the Calla lily in the United States, caused by Bacillus 

 aroideae (Townsend). The disease is present in the bulb, 

 leaves, and flower-stem. The white substance of the bulb 

 becomes brown and watery. The leaves and flower-stem are 

 spotted with a dark colour. The plant is eventually killed. 



Townsend, C, U.S. Dept. Agric, Bur. PI. Industry, 

 Bull. 30 (1904). 



Cherry-tree bacteriosis. A serious disease of cherry-trees 

 caused by Bacillus spongiosus (Aderh. and Ruhl.) is recorded 

 from Germany. Both young and old trees suffer, in some 

 instances to the extent of 50 to 60 per cent. The bark is 

 the part attacked, the injured portions exuding a gummy 

 substance in drops or sometimes in large quantities. Large 

 crevices appear in the bark and extend for some distance 

 inwards, and contain masses of gum and of bacteria. 



The organism is rod-shaped, ends rounded and ciliate. 



