CHAPTER XX 

 JXESHY AND WOODY FUNGI 



Suborder Eubasidu. — The fungi of this suborder are characterized 

 by the undivided (unseptate) basidia, more or less club-shaped with 

 generally four, rarely six, eight, or two apical sterigmata each of which 

 bears a basidiospore (Fig. 92). These fungi are usually fleshy and the 

 spores are borne openly on wrinkles, ridges, giUs, in pores, on spines, 

 or in closed fruits, which open regularly, or irregularly, by splitting. 

 Many of the forms are edible, some are inedible, because of toughness, 

 or woodiness, while others are poisonous. 



Cytology. — Recent studies by Juel (1897), Maire (1900), Ruhland 

 (1901), Harper (1902), Levine (1913) have shown that as a general 

 thing the hyphal ceUs of the mycelium in the HYMENOMYCETES 

 and GASTEROMYCETES are binucleate, and sometimes, as in Cop- 

 rinus radiatus, uninucleate. The cells of the young carpophore are 

 binucleate, but as the fruit body matures, the majority of the cells in 

 the stipe and pileus are multinucleate, but this condition arises from 

 the amitotic fragmentation of the two nuclei originally present in each 

 cell. The subhymenial cells from which the basidia spring and the 

 paraphyses are always binucleate. AH the cells, which are concerned 

 directly with the production of basidiospores, are binucleated through- 

 out their development. The multinucleated condition above noted 

 arises in cells of strictly limited development and are found in the organs 

 of nutrition, support, transportation, etc. Maire found that the pairs 

 of nuclei divide simultaneously, as conjugate nuclei, so that in the suc- 

 cessive cell generations which arise in the development of the carpo- 

 phore the two nuclei in each cell are of widely separated nuclear ances- 

 try, dupHcating exactly the condition found in the rusts previously 

 described. The young basidium contains only two nuclei just as in 

 the teliospore of the rust. These two nuclei fuse to form the primary 

 nucleus of the basidium which then divides twice to furnish the nuclei 

 for each of the typically four basidiospores. Levine (1913) who has 

 studied this nuclear division in a number of species of Boletus, finds the 



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