278 



Introduction to Botany. 



reproductive bodies. Portions of the branched filament 

 become cut off by cell walls, and these demarked portions 



Fig. 140. 



Stages in the life history of Mucor mucedo. A, an entire plant bearing sporangia 

 on upright stalks. B, i and 2, a sporangium before and after breaking open to 

 discharge the ellipsoidal spores; 3, the upper part of the stalk after the sporan- 

 gium has broken away ; 5, a germinating spore which is to produce a plant like 

 A. C, I, two conjugating branches of the thread-like mycelium ; 2, a later stage, 

 showing two end cells demarked by cell walls; 3, a later stage where the wall 

 separating the two end cells from each other has become dissolved, so that the 

 contents of f.ie two cells have fused to form a resting spore ; 4, the mature rest- 

 ing spore ; 5, .he germinating resting spore giving rise to a single sporangium 

 bearing relatively few spores, as shown in B, 4. After Brefeld. 



send forth branches which grow outward from the sub- 

 stratum, sometimes to a distance of several centimeters, 



