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' On October 30th last, at Horsley, I came across a large 

 pine stump, from whose decaying wood a sheet of creamy- 

 white Plasmodium was pouring over the bark. It had already 

 covered about four square feet of one side of the stump. 

 Cutting two pieces of bark, well covered with the plasmodium, 

 I placed them in tin boxes, of which one had the back and 

 front perforated with small holes, forming the initials of the 

 firm of tobacco manufacturers by whom it had been sent 

 out. On reaching home this particular specimen was photo- 

 graphed life-size and replaced in the box, care being taken 

 that there should be no contact with the sides, as it was 

 intended to again photograph it when the ultimate stage was 

 reached ; and it was therefore desirable to remove it without 

 any risk of breakage. The next morning I was surprised to 

 find that a considerable portion of the plasmodium had 

 bridged the small space between bark and box, poured through 

 the perforations, and formed a new mass on the front of the 

 box, as shown in the second photo. A much smaller quantity 

 had found its way through the similar perforations at the 

 back, which was in shadow. The lid had been tightly closed, 

 thus excluding all light save that which found its way through 

 the perforated initials. It appears, therefore, that the 

 organism is highly phototropic ; and it is no doubt in response 

 to light attraction that the individual swarm-cells emerge 

 from the recesses of the rotten wood to form the plasmodium. 

 Though by close watching with the unassisted eye I could 

 not detect the actual movement of this shining mass, yet it 

 was easy to see after brief intervals the advance that had 

 been made, whilst the filmy strands behind indicated the 

 area that had been abandoned. 



" Ultimately the whole of the plasmodium flowed through 

 to the exterior of the box, and consolidated itself into two 

 cushions {cethalia), as shown in the third photo, the outer 

 cells flattening to form a tessellated purple-brown crust, whilst 

 the inner ones broke up into the capillitium threads and 

 soot-like spore-mass. 



■'Thesecond sample I handed to Mr. West for microscopical 

 examination, and he has kindly made photo-micrographs, 

 giving enlarged views of the plasmodium stage ( x 5 and x 10), 

 the crust of the gethalium ( x 5 and x 10), the very character- 

 istic capillitium threads, with their lime-knots (x 450), and 

 the spores (x 375 and x 600), All that is now needed to 

 complete the series are views of the germinating spores and 

 the swarm-cells in the pre-plasmodium stage, and these I 

 hope Mr. West will also succeed in giving us later." 



