40 ELEMENTARY BIOLOGY. [CHAP. 



e. The germination of the Conidia, and building up 

 of the Mycelium. 



a. Sow some conidia in Pasteur's fluid in a watch-glass ; 

 protect from evaporation, and watch the development 

 of the mycelium (examine the surface with a low 

 power) ; then the formation of aerial hyphae ; finally 

 the production of new conidia. 



b. [Sow Conidia in Pasteur's fluid in a moist chamber, and 

 watch from day to day ; note the formation of eminences 

 at one or more points on a conidium ; the elongation of 

 these eminences to form hyphae; the branching and 

 interlacement of the hyphae.] 



B. MUCOR MUCEDC. 



1. Place some fresh horse-dung under a bell-jar and 

 keep moist and warm; in from 24 to 48 hours its 

 surface will nearly always be covered by a crop of 

 erect aerial mucor-hyphae, each ending in a minute 

 enlargement (sporangium) just visible with the un- 

 assisted eye : it is this first crop of hyphae and spor- 

 anges which is to be examined. 



2. Snip off a few of the hyphae with a pair of scissors, 

 mount in water, and examine with i inch obj. 



a. Large unbranched hyphae, each ending in a 

 spherical enlargement (sporangium). 



3. Examine with J obj. 

 a. The hyphse. 



a. Their size; they greatly exceed the hyphae of 

 Penidllium both in length and diameter. 



P. Their structure ; homogeneous sac, granular 

 protoplasm, vacuoles : septa absent except 

 close to the sporange. 



