THE MYXOMYCETES 281 



from one and a half to two minutes, then it slackens 

 and stops altogether for an instant, only to recommence 

 with equal energy in the opposite direction. This 

 internal flow is closely related to the locomotion of the 

 whole plasmodium, for it is found that the current 

 lasts longest in that direction in which the plasmodium 

 is advancing. 



The movements do not go on at random, but take 

 a definite direction in accordance with the needs of 

 the organism. Thus an active plasmodium, if the wood 

 be wetted on one side of it more than on the other, 

 will move towards the damper side ; if, however, the 

 Myxomycete be about to form spores (for which moisture 

 is not favourable) it will move the opposite way, in the 

 dry direction. Generally speaking, a plasmodium will 

 try to avoid intense light (which no doubt has a bad 

 effect, as in the case of the Bacteria) ; for the purpose 

 of spore-formation, however, it will leave any dark 

 recess of the wood in which it may be hidden, and 

 seek the light. 



This particular Myxomycete, Badhamia utricularis, 

 feeds on living Fungi, especially on certain members 

 of the Hymenomycetous family, which grow on decaying 

 wood. If a piece of one of these Fungi be placed in 

 its way, the advancing margin of the Badhamia at once 

 begins to flow over it, and the whole plasmodium will 

 turn aside in the direction of the prey. Individual hyphaB, 

 or small pieces of the Fungus, become enclosed in vacuoles 

 in the protoplasm of the Badhamia and digested, their use- 

 less remains being afterwards disgorged and left behind 

 on the track. This way of feeding, by taking solid food 

 into the body, and then digesting it, is characteristic of 

 animals, and is not known among true plants. The Myxo- 



