NOTES ON NORTH AMERICAN HYPO- 

 CREALES— III. TWO NEW SPECIES 

 WITH STUDIES OF THEIR LIFE 

 HISTORIES 



Fred J. Seaver 

 (With Plate 30, Containing 13 Figures) 



So little is known of the life histories of the polymorphic 

 species of the present order that any information which can be 

 gained as to the complementary phases where the ascigerous stage 

 is known is of much interest to mycologists. Not only is this 

 true because of the fact that it gives us the knowledge of the 

 life history of the individual species studied, but it furnishes at 

 least a clue as to the direction in which to look for the com- 

 plementary stages in other species where only the perfect or im- 

 perfect stages are known. 



In my own studies of the Hypocreales, I have been much in- 

 terested in the group of so-called imperfect fungi known as the 

 Verticillieae and their perfect stages, several of which have been 

 noted among nectriaceous plants. The Verticillieae are char- 

 acterized by the verticillately branching conidiophores, the plants 

 resembling in this respect Penicillium. The conidia are hyaline 

 and borne either singly or in chains. The conidiophores often 

 spring from a more or less well-developed stromatic base, giving 

 the whole a floccose appearance of a whitish or pinkish color. 



Among the Nectriaceae, the first species studied which was 

 found to be associated with a Verticillium was Creonectria 

 ochroleuca (Schw.) Seaver. This species has proved to be very 

 common and a number of synonyms have been worked out. The 

 examination of the types or cotypes of several of these synonyms 

 has shown them to be associated with a Verticillium. Spegazzini 

 seems to have been the first to call attention to the association 

 of this Nectria with a V erticillium in his description of Nectria 

 vulgaris Speg., which species is a synonym of the above. The 



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