REPORT OF THE SOCIETY 47 



groups on their reactions to these strains; in the resistant group, he only found 

 two varieties, Well's Red Kidney and White Imperial; a second group was resis- 

 tant to alpha but not to beta: a third was resistant to beta but not to alpha; and 

 the fourth was susceptible to both strains. 



Edgerton and Moreland (5) in 1916 reported on the results of inoculations 

 made with eight cultures and three reisolations from them, and considered from 

 the infection results on the varieties used, that they had three strains of the pa- 

 thogen One group was infectious on all but one variety used, viz: Large 

 White Kidne}', a second that infected Boston Pea heavily and Red Kidney 

 lightly, and a third that infected Red Kidney severely but the Boston Pea 

 lightly. 



Burkholder (3) working in New York State reported on an isolation made 

 from beans of the White Imperial variety that Barrus considered resistant; and 

 found that he had a strain that was infectious on the White Imperial and which 

 completely killed Well's Red Kidney, considered as the most resistant variety, 

 in the seedling stage. He found, however, that the ^Michigan Robust which was 

 resistant to the beta strain was also resistant to the new one. This strain was 

 denoted by the Greek letter gamma. Burkholder considered that this new strain 

 arose as a mutation from the beta. 



The latest work was done by Leach (6) at Minnesota, who, as a result of 

 inoculations made with fifteen cultures on sixteen varieties decides that he can 

 distinguish eight plwsiological species and he set up a dichotomous key for 

 tracing these species by a series of inoculations on seven varieties of beans. He 

 attempted to find some other method of identifying these species but decided 

 that the differences noted did not remain constant enough to use with certainty. 



Experimental Work. 



The present work has been largely along the lines of a study of the physiolo- 

 gical specialization in CoUetotrichum lindemidhiamim in Eastern Canada, both 

 as to the number of species present and the frequency of occurrence of any 

 such species. Attempts were made to secure the perfect stage but they were 

 imsuccessful. 



The cultures used were largely collected from the Macdonald College 

 farm from as wide a range of bean varieties as possible. Letters were also sent 

 out to various places in Ontario, New Brunswick and Nova Scotia and samples 

 of diseased pods and beans received. It was found impossible to isolate CoUeto- 

 trichum from over one-half of these, due to the samples being heavily conta- 

 minated with secondar}' organisms before being received. A number of lesions 

 not unlike anthracnose were noticed on Soy beans growing in the same patch 

 with garden beans, but all attempts to isolate C. lindemxiihianum failed. It is of 

 interest to note that. a bean pod from Nova Scotia, apparently infected witM 

 anthracnose of a very severe type only gave rise on culturing to Phyllosticta 

 phaseolina Sacc. It was similar macroscopically in culture, and on the seedlings 



