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THE JOURNAL 



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OF THE 



^uekctl M^icrosc apical dt^htb. 



ON THE FORMATION OF SPORANGIA IN THE 



GENUS STEMONITIS. 



By a. E. Hilton. 



{Read October 26th, 1915.) 



Plate 1, Figs. 1-4. 



One of the most aoandant forms of Mycetozoa in all parts of the 

 world is Stemonitis ; a genus easily recognisable by the dark- 

 brown sporangia, usually 0*5 to 0*75 of an inch high, generally 

 crowded together, which look something like diminutive bull- 

 rushes, on slender black stalks. 



Familiar as these are to some of our members, it is probable 

 that not many have had an opportunity of watching the actual 

 transformation of a plasmodium into sporangia. This process 

 is so interesting that you will, I think, like to have a description 

 of it, taken from my notes made at the time of a recent obser- 

 vation. By way of preface, it is well that I should remind 

 you that in Stemonitis the stalk is continued upward as a 

 columella nearly or quite to the apex of the sporangium. From 

 this columella the capillitium branches in all directions, and 

 surrounds the sporangium with a surface network of extremely 

 delicate meshes, through which the spores finally escape. 



In the middle of August last, after six weeks of frequent heavy 

 rains, I took advantage of unusually favourable conditions, and 



JouRN. Q. M. C, Series II.— No. 78. 1 



