37 6 APPENDIX. 



3. The pulverulent appearance on the younger leaves, due to 



spores. 



4. Demonstration. Scrape a bit of the mycelium from the sur- 

 face of the leaf after moistening it for a few minutes with a 5 % 

 solution of potassic hydrate. Mount and show (a) the colorless 

 branching hyphae ; (b) the erect branches bearing the spores ; (c) 

 the spores. 



7. Examine as before one of the older leaves. Observe the 

 yellowish dots scattered over the mycelium, the immature fruits. 

 (*T[ 401, fig. 337.) Associated with these the black mature fruits. 

 These contain sporangia with spores. (^[ 317, fig. 223.) 



8. Demonstration. Mount and crush under cover glass some 

 mature fruits ; show the sporangia (asei) and their contained 

 spores. (Fig. 224.) 



D. CUP-FUNGUS (Peziza sp.). 



1. The mycelium penetrates the earth or rotting wood on which 

 the fructification appears and cannot be dissected out. Only the 

 reproductive parts (If 317) are to be examined. Observe the size, 

 shape, and color of the cup. The red and orange cups usually 

 lose their color in preserved specimens. 



Cut a thin section from a piece of the cup at right angles to 

 inner surface. Mount. Observe 



2. The dense upper layer of parallel hyphae {hymenium), with 

 rows of black specks. The latter are the spores in the long 

 parallel sporangia {asci). (^[ 317, fig. 222.) 



3. The lower layer, less dense, of tangled hyphae. 



4. Demonstration. In a very thin vertical section show (a) the 

 hymenium, with paraphyses, asci, and ascospores ; (6) the looser 

 lower layers of interwoven hyphae. 



E. LICHEN {Physcia stellaris). 



Soften the plants by soaking them in water for a few minutes. 

 Observe 



1. The mycelium, forming a connected leaf-like lobed thallus. 

 Compare as many other forms as are available. (^[ 54a, fig. 225.) 



2. Compare the color when dry and wet. In the latter condi- 

 tion, the mycelium is more translucent and the imprisoned green 

 algae show through more plainly. (Figs. 55, 377.) 



3. The tufts of hyphae extending from lower surface to bark, 

 the holdfasts or rhizines. 



