Apr. 8, 1918 Relation of Soil Fungi to Potato Diseases 81 



DETAILED CONSIDERATION OF THE FUNGI ISOLATED 

 ASPERGILLUS 



One strain of Aspergillus was isolated once from sample 3. This was 

 identified by Dr. Thom and Miss Church (see p. 93). 



ABSIDIA 



Three species of the genus Absidia were identified as follows: A. 

 glatica Hagem, isolated once from sample 2 and once from group C; ^. 

 spinosa Lender, isolated once from sample i ; and one unidentified species, 

 isolated once each from samples 1 and 3. These were identified by Mr. 

 Zundel 



CHAETOMELLA 



One species of the genus Chaetomella w^as twice identified, once each 

 from group B and sample 2. This species is briefly described as fol- 

 lows: Mycelium white to gray or darker; perithecia separate, scattered 

 on the mycelium but without distinct subicle, ovate-globose, 50 to 125 /* 

 in diameter, black, beset with straight or curved bristle-like black hairs, 

 100 to 250 /x long, about 7 fj. in diameter, septate, the septa distinguish- 

 able with difficulty; spores elliptical, olivaceous, 8 to 15 by 4 to 8 /x; 

 character of sporophore uncertain. 



FUSARIUM 



Fourteen species of the genus Fusarium were isolated and identified. 

 Because of the economic importance of this genus very careful attention 

 was given each form isolated and in their identification, except where 

 otherwise indicated in the following pages, authentic cultures were 

 available for comparison. The writer is indebted to Mr. L. L. Harter, 

 of this Office, for cultures of Fusarium dimerum Penz., F. subpallidum 

 Sherb., F. acuminatum EH. and Ev., emend WoUenw. F. discolor var. 

 triseptaium Sherb., and F. sanguineum, Sherb., as well as for many other 

 cultures used in the comparisons, and to Dr. H. A. Edson, of this Office, 

 for cultures of several strains of Fusarium which, it was thought, might 

 be identical with certain of those isolated. Five of the strains isolated 

 apparently differed from all species heretofore described and are herein 

 presented as new species. The species isolated are as follows : 



Section Dimerwm ' 



Fusarium affine Faut and Lamb {4, p. 68; 13, v. 14, p. 1125; 14, p. 126). 



The organism isolated agreed very closely with the original description 

 given by Fautrey and Lambotte (4) and appeared to be very similar, 

 both in microscopic characters and in habit of growth, to the strain 



' The arrangement and grouping is after the plan suggested by WoUenweber {20). 



