A Monograph of the Myxogastres. 19 



in the vacuoles in which they lay, until at length all trace of 

 them had disappeared together with their containing vacuoles, 

 and only the contracting vacuole remained in the homogeneous 

 granular substance of the swarm-cell. 



"At the commencement of the observation this granular 

 protoplasm was much more turbid than at the close, when it 

 was remarkably hyaline ; the swarm-cell appeared also to have 

 increased in size, though it was difficult to determine by 

 measurement in consequence of its changing form. No rejec- 

 tion of refuse matter took place while the observation lasted. 



" In the same preparation I watched a swarm-cell creeping in 

 a straight line with the strange snail-like movement, so difficult 

 to understand. In its course it came to a small group of motion- 

 less bacilli lying against the glass; immediately it changed 

 its linear form and spread itself out, covering four of the bacilli. 

 In about two minutes it resumed its former shape and movement 

 and crept away, carrying off two of the bacilli in vacuoles. 



" These observations seem to confirm the opinion of De Bary, 

 that the organisms under consideration should be classed among 

 the animal rather than the vegetable kingdom, which led him 

 in 1858 to adopt the term Mycetozoa in place of that of 

 Myxomycetes for the group. When a creeping swarm-cell is 

 watched, with the projecting cilium placed immediately in 

 advance of the nucleus, which never shifts its position, and 

 when, as in the last-mentioned case, we note the manner in 

 which the vibrating extremity of the cilium appeared to detect 

 the presence of the bacilli before the swarm-cell spread itself 

 over them ;. again, when we observe the creeping action suddenly 

 change, and raising itself from the decumbent attitude, with a 

 few lashing strokes of the cilium the swarm-cell releases its 

 foot-hold and swims away; and when to these remarkable 

 movements is added the process of ingestion which has been 

 described; we cannot but feel the force of the conclusion at 

 which De Bary arrived, if indeed a distinct line of demarcation 

 between the two kingdoms can be said to exist." x 



The brilliant and pure colours presented by the plasmodia of 



1 Notes on Clwndrioderma difforme and other Mycetozoa; Ann. Bot., 

 Vol. IV. No. xiv. (May 1890), pp. 281298, 1 pi. 



