CIIROMOGENIC FUNGI WHICH DISCOLOR WOOD. 



83 



Primary Conidia. 



After the primary conidia have been detached and sep- 

 arated from the mucus there is in many species nothing to 

 distinguish them from the secondary conidia. In fact, the 

 real difference usually in the two forms is whether they 

 are borne on a single hypha, or on hyphae united in a 

 stroma. The agglutinated cluster on a single stalk of one 

 hypha corresponds morphologically to the mucous-covered 

 head (pi. 7, f . 2, 5). The latter are more persistent, and 

 retain the conidia for a much longer time. A secondary 

 growth of the stromata has been noted in some species 

 after the first spores have been formed, and have dropped 

 away, in which there are formed branches from the end of 

 an old stalk, growing out 

 from the apex. (See figure). 

 Each of these s u b s i d i a ry 

 stalks is composed of a num- 

 ber of parallel filaments, or 

 hyphae, which in turn 

 branch at the outer ends and 

 form masses of conidia like 

 the original head, only small- 

 er. Such growths take 

 place on rich, starchy media 

 like cooked potatoes. On 

 cultures on rice and potato 

 an abortive type of stromata 

 is often formed in the shape 

 of somewhat flat, branching 

 stalks, which grow much tall- 

 er than the fruiting form, 

 but bear no conidia. This 

 abortive form resembles very 

 much the original description 

 of the sterile fungus Anihina Fr., which is probably a 

 form of Graphium. 



G. KUMORPIIUM, X 50. 



Proliferation of stroma. 



