Apr. 29. i9i8 Anthracnose of Lettuce 263 



hart having determined the fungus from Selby's collections. The fungus 

 was reported as being quite prevalent in Ohio greenhouses that year and 

 as causing considerable loss to lettuce growers. In a succeeding publica- 

 tion Selby (9) repeated the statements of former bulletins and stated 

 that the fungus had since been discovered at other points in the United 

 States. 



No doubt the most important contribution to the literature of this 

 disease was that of Appel and Laibach in 1908 (i). In the Province of 

 Brandenburg, Germany, an epidemic caused by the fungus called Mars- 

 sonia panattoniana in the spring of 1 907 caused many growers to destroy 

 thousands of plants. It is noteworthy that the fungus appeared in the 

 open, while American observations dealt with the disease in greenhouse 

 plants. Appel and Laibach made important notes on the morphology 

 of the fungus, grew it in pure culture, and made inoculation experiments 

 with spores from the diseased host. 



Dandeno in 1907 (4) from examinations of Michigan material came to 

 the conclusion that the fungus, called by him "Marssonia perforans," 

 was not properly classified as Marssonia, but was rather a species of 

 Didymaria. 



Kirchner, in 1906 (6, p. 376, 389), without citing his authority, records 

 the disease from Holland and Italy on endive, as well as lettuce. 



Aside from repetition of statements from former literature in the gen- 

 eral handbooks of plant diseases, no other publication on this disease or 

 its causal organism has come to the writer's attention. 



DISTRIBUTION OF THE FUNGUS 



The distribution of the fungus is no doubt wide. No record exists of 

 its presence in Europe, except in Germany, Holland, and Italy. Meager- 

 ness of accounts may be responsible for this lack of record. From the 

 notes in the literature, the fungus is known from Ohio and Michigan. 

 The Ohio records date from 1895. The first Michigan specimens were 

 collected on March 20, 1897, at Grand Rapids, by B. O. Longyear. Since 

 then the fungus has been found repeatedly at various parts of the State. 

 During an excessively wet June in 191 6 it was found at East Lansing 

 as a serious pest on lettuce grown in the garden.^ Early in 191 7 it was 

 obser\^ed by the writer in a greenhouse at Ithaca, N. Y., where 5 to 10 

 per cent of the plants were a total loss, and many of the remainder were 

 so badly affected as to require the stripping of the outer leaves. Since 

 that time it has been reported from various parts of New York State by 

 Mr. H. W. Dye, Dr. Charles Chupp, and Dr. I. C. Jagger. Dr. Jagger 

 informed the writer that he had. noticed the disease in previous years in 

 New York State. 



' The writer is indebted to Dr. G. H. Coons for this report. 



