22 The Mycetozoa, and 



time to time a granule will be seen to advance, and then 

 another granule, and so on till the line of the land has 

 been pushed out into the foreshore, and the foreshore itself 

 is moved forward into the sea. In this way the front line 

 of the whole plasmodium advances, and as the rear of the 

 plasmodium is drawn back in the line of advance as the 

 front line is pushed forward, the whole body of the plas- 

 modium gradually changes its place and moves forward. 



It is a very striking thing to watch these forward move- 

 ments of the granules. You seem to see in a minute and 

 most intimate form the locomotion of living things ; and, 

 moreover, you perceive an internal movement of part, 

 resulting in a movement in space of the whole organism. 

 Mr. Spencer has said that " we have as yet no clue to the 

 mode in which molecular movement is transformed into 

 the movement of masses in animals." Does not the 

 motion which we have described offer, if not a clue, yet a 

 visible example of such transformation ? Be this as it 

 may, the mystery of motion remains just the same ; there 

 is the same antinomy between sense and reason the one 

 says that there is motion, the other that it is impossible. 



" Io dird cosa incredibile e yera." 



It must not be supposed that it is only on the surface of 

 dead wood or leaves that the plasmodia of myxies move. 

 Sometimes, and especially under the influence of cold, 

 they retreat downwards, and the Fuligo, a species which 

 lives on tan and is known as the flowers of tan, will, 

 under this influence, disappear from the surface of a heap 

 and retire to the bottom of it. Cold or other unsuitable 



