Algae, Fungi, and Lichens. 267 



159. Make sections through the enlarged bladder-Uke 

 portions of the plant. Do they contain air or water ? 

 What is their evident purpose ? Make sections through 

 the other portions of the plant, and examine under the 

 microscope. Although the plant has a brown color, it 

 really contains chlorophyll, whose character is masked by 

 the brown coloring matter associated with it in the chloro- 

 plasts. By what means is this plant held in proper condi- 

 tion to catch the sunlight.'' 



FUXGI. 



160. Moisten stale bread in water and place it under a 

 bell jar in a warm place. To be more certain of obtaining 

 what is wanted, place under the bell jar some lemon pulp 

 and rind from which the juice has been squeezed, or pieces 

 of partly decayed sweet potato or banana. Various sorts 

 of growths will appear, but the filamentous growths which 

 in a few days bear minute spore cases on thread-like stems, 

 are the forms desired for this study. 



161. Determine whether the filaments making up the 

 body of the growth penetrate the substratum or simply lie 

 on its surface. Examine with a lens the spore cases, or 

 sporangia, of different ages. With a pair of forceps, care- 

 fully pull off sporangia of different stages of development, 

 and mount under a coverglass in a drop of 70^ alcohol. 

 (Alcohol is used instead of water because air bubbles 

 adhere to the material when water is used, but after mount- 

 ing in alcohol a drop of water may be placed on the slide 

 in contact with the coverglass, and as the alcohol evapo- 

 rates the water will take its place.) Note the appearance 

 of the spores in the sporangia of different ages. Why do 

 the old sporangia appear black ? 



162. Soak a cubical block of stale bread in water, sow 



