Some Questions which they Suggest. 29 



frequently occurs after the ingestion of food, and in a few 

 minutes the bacillus was bent double, and the vacuole 

 decreased in size. These observations of Mr. Lister seem 

 to prove that the view of De Bary that the swarm spores 

 take in nutriment only in a fluid state cannot be upheld. 

 These processes are depicted in Fig. 3, which is repro- 

 duced by the permission of the Council of the Linnean 

 Society and of Mr. Lister. 



It is a curious fact that where a plasmodium on its 

 march meets with a microcyst of its own kind, it has 

 been observed to commit an act of cannibalism to treat 

 it as if a foreign body, and to enclose it in a vacuole, 

 and then absorb it. Probably the presence of the mem- 

 brane prevented fusion until it was removed by an act of 

 digestion. 



REJECTION OF MATTER. Mr. Lister has been equally 

 successful in observing the method pursued by the plas- 

 modium in the rejection of undigested matter. He fed, 

 and I am afraid overfed, the plasmodia of Badhamla 

 utricularis on thin slices of fungus, and when a plasmodium 

 had become loaded with food material, many of the large 

 vacuoles became charged with undigested matter, which 

 assumed the appearance of a dark ball, and he " repeatedly 

 saw these vacuoles push out as bubbles to the surface of 

 the plasmodium and burst, discharging a cloud of refuse, 

 consisting of fragments of starch and broken fungus 

 hyphoe, into the water." But when the plasmodium creeps 

 over glass, he observed the rejected matter, with a certain 

 amount of plasmodium substance, to be left " on each side 



