Ixxiv THE BEGINNINGS OF LIFE. 



of Professor Hartig 1 . The spermatozoids or phytozoa from 

 the antherida of these plants first assume the forms of 

 Ehrenberg's genera, Spirillum, and Vibrio. They do not 

 last long, since after forty-eight hours all of them are seen 

 to have become disarticulated. The whole drop of water in 

 which they float is then rendered turbid by numberless 

 actively-moving globules, similar to Monas crepusculum, 

 which, according to Professor Hartig, are always de- 

 veloped from the broken-up fragments of the Spirilla and 

 Vibriones. But after forty-eight hours 'groups of several 

 hundred may frequently be seen in which the primary active 

 motion has ceased. Shortly afterwards, a sharply-defined 

 hyaline skin is formed round these groups, and as it would 

 seem, by the amalgamation or conjunction of the exterior 

 molecules. By this means the young Amceba (Proteus) is 

 formed. This transformation takes place pretty regularly 

 towards the end of the third day. The original size of the 

 Amoeba is -g-JV i n diameter.' In the course of three or four 

 days it increases in size, and its movements are very slow. 

 It possesses a vesicle in the posterior part of its body, and 

 resembles the Amoeba princeps of Ehrenberg. The further 

 changes are thus described : ' After four or five days the 

 Amoeba assumes a spherical shape, and becomes motionless, 

 the vesicular body expanding and contracting rapidly as 

 before, in a manner similar to what takes place in many 

 VorticellcB. These spherical motionless Amoebce are then, 

 for the most part, united by a mucilage into groups of from 

 ten to twenty. ... In about a fortnight after the com- 

 mencement of the experiment a green point appears in the 

 interior of the spherical colourless Amoeba; this point 

 gradually increases in size till it fills up the entire hollow of 

 the Amceba, and, after becoming covered with a cuticle, it 



1 See Translation in ' Journ. of Microsc. Science,' 1855, p. 51. 



