196 



STATE BOARD OP AGRICULTURE. 



STRUCTURE AND CLASSIFICATION OF FUNGI. 



If a small fragment of some fleshy fungus is examined with a micro- 

 scope of high magnifying powers, it will be found to be made up of inter- 

 woven, branching, tubular filaments, often with delicate partitions divid- 

 ing the tubes into cells. Thus the body of the fungus is shown to be con- 

 structed from the same kind of threads as the mycelium, in fact, it is a 

 continuation of the mycelial filaments closely interwoven and often grown 

 together. In the densest portions of some very hard fungi the mycelial 

 filaments are not only interlaced and grown together, but are divided 

 into short cells, by numerous cross partitions, while the walls are much 

 thickened. In soft fungi the mycelial tubes are loosely interwoven and 

 have thin walls with fewer partitions. 



Fig. 5. 



Fig. 6. 



Fig. 7. 



Figure 5. Small portion from the stem of a Morel showing cell-fllaments. Highly magnified. 



Figure 6. Small portion of a section through the spore-bearing layer (hymenlum) of a mush- 

 room which produces its spores on the ends of cells called basidia. (a) spores; 

 (b) a basldlum; (c) sterile cells. Highly magnified. 



Figure 7. Small portion of a section through the spore-bearing part of a Morel, in which the 

 spores are produced in little sacks known as ascl. (a) an ascus; (b) an ascus dis- 

 charging Its spores; (e) sterile cells. Highly magnified.— Original.) 



Fungi are classified according to their various modes of spore pro- 

 duction. The flesh}' fungi belong in two great classes' known as Basi- 

 diomycetes and Ascomycetes. In the former class the spores are formed 

 on the ends of little elongated cells called Basidia, while in the latter 



