THE SIMPLER ORGANISMS 101 



Watch the development in the several plates and com- 

 pare results. 



The record of this study may consist of notes and diagrams 

 of the things observed. 



THE SLIME MOLDS. 



These are organisms of mixed character. In certain 

 phases of their existence they exhibit animal functions ; in 

 other phases, only plant functions. In textbooks of 

 zoology they are called Mycetozoa ; in most texts of botany, 

 Myxomycetes. 



Slime molds live during the greater part of their life as 

 spreading masses of naked protoplasm, which slowly creep 

 about through the tissues of rotten logs, stumps, leaves, etc., 

 like giant amoebas. They are soft and slimy to the touch, 

 and are of a consistency about like that of the white of an 

 egg. Their prevailing tints are yellow, brown, ecru or 

 purplish, or almost any color except green. They are 

 usually small, but with plenty of food and moisture, a single 

 plasmodium often grows to be a foot across. They shun 

 the light and are always to be looked for in sequestered 

 places. During nearly the whole of the growing season, 

 from early summer until late autumn, they may be found in 

 deep mossy woods, and in shaded places by permanent 

 springs. On damp, muggy days following warm summer 

 showers the plasmodia may be found, outspread upon the 

 surfaces from which they draw their nourishment. They 

 are saprophytes. They feed on the dissolved organic 

 substances of decaying stems and leaves. They are 

 always found associated with fungi of similar habits, but 

 unlike the fungi they may also take solid food, engulfing 

 it as does an amoeba by surrounding it with outflowing 

 protoplasm. 



Each plasmodium is a single multinucleate mass of 

 protoplasm, without separating cell walls. The nuclei 



