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TEXTBOOK OF BOTANY 



non-septate hyphae. As a group they were named Fhij corny cetes (Gr. 

 phykos, alga; mykes, fungus) because they appeared to resemble algae 

 more closely than other fungi. One group of phycomy cetes, the Ento- 



FiG. 243. Enlarged drawings of the reproductive structures of a downy mildew 

 parasitic within tobacco, tomato, eggphxnt, and pepper. The myceHum is inter- 

 cellular. A, a branched conidia-bearing hypha protruding from a leaf through one 

 of the stomates; B, germination of conidia; C, stages in the development of a 

 conidium at the tip of a hypha; D, the hypha from a germinating conidium has 

 grown into a leaf through a stomate; E-I, stages in the development of a zygote 

 by sexual reproduction. From North Carolina Agricultural Extension Service. 



mophthorales, is of interest because many of the species live as parasites 

 in insects. 



The powdery mildews, on the other hand, have septate hyphae. Their 

 reproductive structures (ascocarp, ascus, and ascospore) also differ 

 from those of downy mildew. More than 25,000 species of fungi produce 

 ascospores, and as a group thev are called Ascomy cetes. Other examples 

 of them are yeast, blue and green molds, cup fungi, morels, and truffles. 



