FUNGI. 471 



MYXOMYCETES. 



When young, naked, mobile, in consequence of which the masses 

 of plasmodium have a changing form. These masses, at the time 

 of fructification, sometimes dividing themselves into single parts, 

 are transformed into motionless fruits. Eruit either irregular in 

 form (plasmodiocarp) or regular (sporangium). Sporangia, through 

 fusion and union, produce now and then compound fruits (dEtha- 

 lium) usually of considerable dimensions, of regular or 

 irregular form, naked, or covered with a common coat (cortex). 

 Spores produced within the fruit through free cell-formation, or 

 on the surface through division. The contents of the spores at 

 the time of germination give rise to either at first a naked zoospore, 

 provided with a nucleus, a cramped vacuole, and long cilia, or to 

 an amoeboid. These zoospores or amoebae, flowing together in 

 masses, give rise to mobile plasmodia. (Rostafinski.} Illustrative 

 G-enera : Physarum, Pers. ; jDidymium, Schrad. ; Spumaria, Pers. ; 

 fStemonitisj Grled. ; Amaurochcete, H. ; Dictyostelium, Bref . ; Cri- 

 braria, Pers. ; lleticularia, Bull. ; Trichia, Hall ; Lycogala, Mich. 



Structure and Life-history. The Myxomycetes present in the course of 

 their life phenomena so entirely different from those occurring in other 

 Thallophytes, that it has, with much reason, been proposed to separate 

 tliem from this great group, and to place them among animal organisms, 

 to which at least one stage of their existence shows the greatest simi- 

 larity. The mobile or plasmodium stage resembles very strongly the mobile 

 amoeba, of the animal qualities of which no doubt has been entertained ; but 

 the fructification is so little like the " encysting " of these animals, or any 

 other process in animal life, and moreover is so fungal in its nature, that 

 this proposition has not been generally accepted. Not only the habit of 

 life, but even the processes of nutrition of the plasmodiam stage are 

 animal. These organisms are to be found in damp situations, on rotting 

 wood, leaves, &c. 



The whole of this subject is so large and many-sided (and its relative 

 importance here is so small), that for details of the life-history of these 

 organisms the student, must be referred to De Bary's 'Mycetozoa,' and for 

 their systematic disposition to Rostafinski's Monograph of the Order. 

 Incidental reference will be found to them under the head of Physiology. 



SCHIZOMYCETES. 



The Schizomycetes, which are the lowest forms of life known, 

 inhabit fluids which contain organic matter. The majority consist 

 of extremely minute cells which neither in their membranes nor 

 contents exhibit any marked characteristics. They are usually 

 present in great abundance wherever putrifying organic matter is 

 found. Among them are included such forms as Bacteria, Sarcince, 

 Vibriones, Spirilla, some of which show a slightly higher organiza- 



