THE BEGINNINGS OF LIFE. 175 



is almost black from the condensation of chlorophyll 

 that has taken place in its substance. c lt is then/ 

 Dr. Hassall says, c that the crisis commences: the 

 superior extremity suddenly becomes protruded, the 

 granular fluid empties itself into the protruded portion, 

 which quickly increases in volume, so that the opposite 

 extremity becomes separated from the filament. At 

 the same time the spore commences to turn on its great 

 axis in such a manner as that all the granules which it 

 contains are seen to pass rapidly from right to left, and 

 from left to right, as though they moved in the interior 

 of a transparent cylinder/ The spore soon completely 

 frees itself from the filament 1 , and c springs with 

 rapidity into the surrounding liquid,' where it swims 

 about with its colourless portion always in advance, 

 and may then be seen to be surrounded by a tolerably 

 thick transparent membrane. It continues revolving 

 on its axis, at the same time that it moves about from 

 place to place. c In general it quickly reaches the edge 

 of the glass as though it tried to escape ; sometimes it 

 stops j then in an instant afterwards it resumes its 

 course.' The cilia which cover the whole surface of 

 the transparent membrane are mostly invisible on 

 account of the rapidity of their movement ; but when 

 their motion is retarded by putting some opium into 

 the water containing the spore, the individual cilia 



1 These remarkable phenomena may occur more than once. Dr. 

 Hassall says, 'I have seen the operation thrice repeated upon the 

 same filament.' 



