148 British Fungi. 



resting Euglena (e) it penetrates into its body, 

 destroying and exhausting it to supply food to the 

 parasite. The parasite then begius to increase in 

 size, the rhizoid-tubes become larger and thicker, and 

 new ones are formed which throw out branches, and 

 attack and destroy any new Euglense which they 

 encounter. In this way a much-branched plant is 

 formed with hair-like terminal branchlets, which 

 connect with the larger main stems, and. through these 

 with the body of the original spore ; the latter has 

 grown in the meantime into a large round or elongated 

 vesicle at the expense of the Euglena, which have 

 been exhausted by the rhizoids. When it has 

 reached a certain size, varying according to the food 

 which has been sujDplied to it_, it shows itself in many 

 specimens to be a sporangium, or if the term is pre- 

 ferred, a 'prosi^orangium. It grows out at one spot 

 into a bluntly and irregularly cylindrical thick tube 

 with a delicate membrane, into which the whole of tlie 

 protoplasm jDasses, and is at once divided into swarm- 

 spores (C). This process of development may be 

 repeated for many generations, and leads to an 

 immense multiplication of individuals if there is a 

 sufficient number of Euglenee within reach. When 

 this has taken place, the course of events changes. 

 The young plants remain for the most part small, and 

 become gametes which conjugate in pairs, each pair 

 forming a zygospore, and these behave as resting- 

 spores. The two conjugating gametes of a pair (D) 

 have no definite position or distance with respect to 

 one another, and are similar in form to the non- 

 onjugating plants. The one (6), which from the 



