288 COLLEGE BOTANY 



nialin.) Examine a grape leaf and note the location of the fungus and its 

 effect on the host. Examine some of the fungus under the microscope and 

 note the conidiophores and conidia spores. 



Exercise 1. tiaccharoitiyces cerevisiw Meyen., or bread yeast. (Put 

 a small piece of an ordinary yeast cake into a glass of water containing a 

 very small amount of sugar. Keep in a warm place for a few hours.) 

 Examine a drop of this mixture under the microscope. Note the size and 

 shape of the cells, the vacuoles and the budding. 



Exercise 8. Microsphcera alni or any other powdery mildew. Note the 

 relation of the fungus to the host. Examine the mycelium and the Mack 

 fruiting bodies under the microscope. Note the appendages. Crush the 

 fruiting bodies by pressing on the cover glass with the rubber of a lead 

 pencil. Note the protruding asci and spores. 



Exercise 9. Nectria ipoma:a Halsted. (This fungus will be found on 

 sweet potatoes in advanced stages of decay.) Examine the fruiting body. 

 Then crush and examine under the microscope. Note the asci and spores. 



Exercise 10. Penicillium sp. (This material can be very readily ob- 

 tained from decaying oranges or other fruits and from many other 

 sources.) Examine under the microscope and note conidiophores and conidia 

 spores. Germinate some of the spores in hanging drop. See Exercise 3. 



Exercise 11. Peziza sp. Examine the entire plant. Examine pre- 

 pared slides and note asci and paraphyses. 



Exercise 12. Lichen. Examine the entire plant. Examine freshly cut 

 sections and note the relationship of fungus and algae. Examine a section 

 through the fruiting body and note the asci. 



Exercise 13. Ustilago maydis Bech., or corn smut. Examine the fungus 

 and note its position and relation to the host. Examine some of the 

 spores under the microscope. 



Germinate some of the spores in hanging drops prepared of diluted 

 boiled stable manure water. (Spores will germinate more readily if they 

 have been frozen.) 



Exercise l'i. Other smuts may be studied in the same manner if cir- 

 cumstances permit. 



Exercise 15. Puccinia graminis Pers., or wheat rust. 



I. Examine a diseased barberry leaf and note the position of the fungus. 

 Examine prepared slides and note the cup-like bodies and the acidio- 

 spores. Also, note the pycnia. 



II. Examine wheat plant and note the reddish spots on the stems and 

 leaves. Scrape some of these spots and examine under the microscope 

 and note the on-e-celled urediniospores. 



III. Examine the wheat plant and note the black patches on the 

 leaves. Scrape off a little of this material^ examine under the micro- 

 scope and note the teliospores. 



Exercise 16. Gymnosporangium juniperi-irirgimiana or rust of cedar 

 and apple. 



I. Examine the leaf or fruit of the apple and note the appearance of 

 the growth. Examine prepared sections and note the aeciospores. 



II. Examine the fungus growths from the cedar. Examine 

 the teliospores. 



Exercise 11. Agaricus sp. Examine a mature fungus, and note cap, 

 stipe and annulus. Examine prepared slides and note the arrangement 

 of the spores. 



