Fungi 



407 



tous plants that are of great economic importance because of the 

 damage that they do to foods during storage or shipment. Like 



Oo^oTiiiim ii 



ArLtheridium 



Conidium 



Hyplia 



Haustorium 

 Plant cell 



Fig. 249. One of the tube fungi, Cystopus, a parasite on leaves of green plants: A, section 

 of pustule developed on a leaf showing fungus producing conidia (under the broken epidermis) 

 and zygotes (below, in the mesophyll of the leaf) ; B, part of fungus dissected out of the 

 mycelium shown in A ; C, mesophyll cell surrounded and penetrated by absorbing hyphae. 

 Cystopus produces swimming spores when the conidia and zygotes germinate. 



bacteria, the spores of molds are in the air and in the dust every- 

 where, and foods of all kinds are thus continually exposed to them. 

 If the temperature is warm and the food is moist, they germinate 

 and, together with bacteria, soon destroy the food. The same 

 measures that will prevent the growth of bacteria in foods will 

 prevent the growth of the molds, which are usually associated 

 with them. 



Bread mold. When a spore of bread mold germinates, a tube- 

 like hypha develops. This hypha soon branches profusely. 

 Some of the branches penetrate the bread and become absorbing 

 organs, others spread over the surface of the bread like the 

 runners of a strawberry plant and at intervals develop clusters of 



