423 



ON THE STUDY OF THE MYCETOZOA. 



By A. E. Hilton. 



{Read June \:>th, 1906.) 



A little over ten years ago, in one of those extempore lecturettes 

 which often prove more instructive than formal papers, Dr. Karop 

 called our attention to the group of organisms which, for eighty 

 years past, has been known to science as Myxogastn 

 Myxomycetes, or Mycetozoa. Fourteen months later this was 

 followed by an admirable " JSTote on Mycetozoa " by Mr. Jeremiah 

 Slade, an old member of our Club, who died last year. This 

 appears in the Quekett Journal for November, 1897. Afterwards, 

 chiefly, I think, from 1899 till 1901, attention was given to the 

 subject by Mr. Dennis and Mr. Filer, this resulting in numerous 

 exhibits, among the most interesting of them being some which 

 showed the remarkable streaming movements of plasmodia. 

 Since then, so far as I know, very little in regard to the 

 Mycetozoa has been done by our Club, and it is because we now 

 have a number of new members that I revive the matter in the 

 present paper. 



For the benefit of those who are unacquainted with the group, 

 and have not seen the specimens shown by me at our meetings 

 during the last few months, I may explain that the Mycetozoa 

 are diminutive organisms, distributed nearly all the world over, 

 which are found in moist places, generally on rotting wood, 

 leaves, grass, moss, fungi, ferns, or other vegetable substances in 

 a state of decay. They are noticeable only in the sporangia 1 

 or spore-bearing stage, when they range in size from ^ to 

 i in. in height, and T i- to J in. in diameter, the more usual 

 dimensions being roughly a height of about ~ in., and a. 

 diameter of about -g 1 ^. From these measurements there are great 

 divergences in certain species; and the general appearance of 

 sporangia may be best suggested by describing them as looking 

 something like minute mushrooms or other fungi, of various 

 shapes and colours. ^Yith the exception of this sporangial stag 

 the phases in the history of the Mycetozoa can only be followed 

 by careful observation and the use of the microscope. Briefly, 

 the life-cycle is this. Large numbers of spores, so >mall as 

 to be usually only about ^^ in. in diameter, rupture while 

 immersed in water, and jelly-specks are liberated, which are 



Journ. Q. M. C, Series IT.— No, 59. 3<> 



