PROTOZOA AND SPONGES. 



379 



You see a flat area of clear jelly, of very irregular form, 

 with sinuosities and jutting points, like the outline of some 

 island in a map. A great number of minute blackish 

 granules and vesicles occupy the central part, but the 

 edges are clear and colourless. A large bladder is seen 

 near one side, which appears filled with a subtle fluid. 



But while you gaze on it, you perceive that its form is 

 changing : that it is not at two successive moments of 

 exactly the same shape. This individual, which when you 

 first looked at it was not unlike England in outline, is 

 now, though only a few minutes have passed, something 

 totally different; the projecting angle that represented 

 Cornwall is become rounded and more perpendicular; 

 the broken corner that we might have called Kent has 

 formed two little points up in the position of Lincolnshire; 

 the large bladder, which was in the place of the Eastern 

 counties, is moved up to the Durham coast, and is, 

 moreover, greatly diminished ; and other like changes 

 have taken place in other parts. 



Lo ! even while speaking of these alterations, they have 

 been proceeding, so that another and a totally diverse out- 



FOKMS OF AMCEBA. 



Successively drawn from one individual . 



line is now presented. A great excavation takes the place 

 of Dorset ; Kent is immensely prolonged ; the bladder 

 has quite disappeared, &0.; but it is impossible to follow 

 these changes, which are ever going on without a moment's 



