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TEXT-BOOK OF FUNGI 



H-shaped structure. Such unions are often abundant 

 where several hyphae run more or less parallel to each 

 other. Such coalescence of germ-tubes is very pronounced 



FIG. 4. Pythium debaryanum, a fungus having aseptate mycelium 

 during its vegetative condition. Septa appear when the fruit is produced 

 by which the latter is cut off from the remainder of the mycelium, i, 

 seedlings of cress (Lepidium sativum) attacked by the fungus; 2, 

 mycelium bearing conidia at the tips of the branches ; 3, sporangia of 

 different ages, also a free zoospore ; 4, an oosphere, with an< antheridium 

 or male organ, which has pierced the wall of the oosphere and inserted 

 a fertilising tube (after this blending of the contents of oosphere and 

 antheridium, the oosphere becomes surrounded by a thick wall, and 

 becomes the oospore, or sexually formed resting-spore) ; 5, a germinating 

 conidium. All figs., except i, mag. 



in the case of germinating secondary spores or pro-mycelial 

 spore in the Uredinaceae and the Ustilaginaceae, where it 



