THE FUNGI. 127 



It is thought that the zygospore formed by some species 

 does not develop. In the case of other species, it is known 

 that, after a period of rest, the zygospore develops hyphse 

 which bear sporangia, but does not develop a mycelium. 

 The spores borne in these sporangia develop in the asexual 

 way into new plants. These new plants multiply in the 

 asexual way, and it is probable that it is only after a num- 

 ber of generations have been produced that the sexual 

 process is repeated to reinvigorate the plant. 



A third process of reproduction sometimes occurs. By 

 this process asexual spores, chlamydospores, are formed 

 in starved filaments of the mycelium. 



The black molds may be sought on decaying moist 

 bread, on preserved fruits, and, in general, on decaying 

 organic matter. 



The molds that develop on and in the bodies of cer- 

 tain insects, especially on flies and caterpillars, are closely * 

 related to the black molds. The growth of these molds 

 constitutes a disease which kills the insect. The mold 

 continues to grow after its death. It is frequently seen 

 fastening its victim to the walls of a room or to a window 

 pane. , The disease is communicated from one insect to 

 another by the spores that the mold produces. The 

 spores are borne about in the air, and if one happens to 

 fall on a moist portion of an insect, the disease results. 

 It is said that in the West Indies it is not at all uncom- 

 mon to see insects related to our wasp flying about with 

 plants, as large as the insects themselves, growing from 

 some part of their bodies. 



MUCOR. PRACTICAL STUDIES. 



Keep a piece of wet bread in a moist chamber until a 

 moldy growth appears on its surface. Some of this 

 growth will almost certainly be Mucor stolonifer. A 



