232 



ELEMENTS OF BOTANY. 



borne. Are these stalks and the mycelium filaments solid or tubular ? 



Are they one-ceUed or several-celled ? 



Mount some of the mature spore-cases in water, examine them with 



the highest obtainable power, 

 and sketch the escaping spores. 

 Sow some of tljese spores i on 

 the surface of "hay-tea," made 

 by boiling a handful of hay in 

 just water enough to cover it 

 and then straining through cloth 

 or filtering through a paper filter. 

 After from three to six hours, 

 examine a drop from the surface 

 of the liquid with a medium 

 power of the microscope (half- 

 inch objective) to see how the 

 development of hyphae from the 

 spores begins. Sketch. 



After about 24 hours examine 

 another portion of the mould 

 from the surface of the liquid 

 and study the more fully de- 

 veloped mycelium. Sketch. 



287. Zygospores. — Besides 

 the spores just studied, zygo- 

 spores are formed by conjuga- 

 tion of the hyphse of the black 

 moulds. It is not very easy to 

 find these in process of forma- 

 tion, but the student may be 

 able to gather from Fig. 200 the 

 nature of the process by which 

 they are formed: a process which 

 cannot fail to remind him of 

 the conjugation of pondscum. 



,FiG. 200. —Formation of Zygospores in a 

 Mould (Mucor Mucedo). 

 1, threads in contact previous to conjugation ; 

 2, cutting oif of tlie conjugating cells, a, 

 from the threads, & ; 3, a later stage of the 

 process ; 4, ripe zygospore ; 5, germination 

 of a zygospore and formation of a spore- 

 case. (1-4 magnified 225 diameters, 5 magni- 

 fied ahout 60 diameters.) 



FUNGI. 

 288. Characteristics of Fungi.— 



-The yeasts and the moulds 

 are humble representatives of an immense multitude of para- 



1 i?he spores of Penicillium will do as well. 



