FUNGOUS DISEASES OF THE CAENATION. 329 



1890, when the writer receiyed from a Michigan florist 

 a number of diseased leaves, with an inquiry as to the 

 nature of the fungus and a remedy for it. The plants 

 had been recently received from Massachusetts, and 

 recognizing the danger of spreading the disease, he was 

 advised to destroy all 

 plants that were badly 

 infected, and to re- 

 move from the others 

 all leaves that showed 

 any pustules, carefully 

 burning both plants 

 and leaves, and then 

 to spray the remaining 

 plants with a fungi- 

 cide. This fungus is 

 closely related to the 

 rust of grains and 

 grasses, and seems to 

 revel upon plants 

 grown in poorly ven- 

 tilated houses, or that 

 have received a check 

 in some way, particu- 

 larly if the plants are 

 syringed at such times 

 as will allow the water 

 to stand on the leaves 

 and branches at night. 

 It enters the plant and 



develops there without fig. lu. carnation rpst. 



manifesting its presence, until a pustule is formed just 

 beneath the epidermis. The spot takes on a grayish ap- 

 pearance, and the membrane soon becoming ruptured, 

 the mass of brownish spores is seen. Tliey are produced 

 in great quantities and appear like fine, brown, dust- 



