202 THE BEGINNINGS OF LIFE. 



again. No other Amoebae or transition states were 

 discovered on this occasion ] . 



Subsequently, however, I saw a similar transformation 

 of motionless corpuscles into ordinary Amoebae taking 

 place in thousands of instances. It occurred in a hay 

 infusion which was examined during one of the summer 

 months. The corpuscles were derived from the pellicle 

 in the same way, and at last separated as colourless 

 ovoid bodies about -g-oW' ^ n diameter. They had a 

 slightly condensed exterior layer, but no distinct bound- 

 ing wall, and seemed to be merely portions of living 

 jelly, in which 5-10 altered Bacteria were imbedded. 

 They gradually increased in size, and very shortly a 

 small solid nuclear body began to appear in the 

 interior of each of them. After the corpuscles had 

 attained the size of T^Vs"" m diameter, their internal 

 substance became more fluid : the previously stationary 

 particles began to oscillate slowly, and they were also 

 smaller and more numerous. Corpuscles which were 

 only a very little larger, began to show slowly-changing 

 irregularities of outline, whilst a vacuole frequently 

 appeared within their substance, lasted about a minute, 

 and then disappeared, to be succeeded by another in 

 a different place. In others the amoeboid changes in 

 shape and movements were now quite distinct, whilst 

 the vacuoles were more persistent, and the nucleus had 



1 Prof. Hartig has also described a similar mode of origin of 

 Amoebae from unicellular organisms, in his observations on the phytozoa 

 of Marchantice. See 'Journal of the Microscopic Society,' 1855, p. 51. 



