PEOTOZOA AND SPONGES. 433 



ening ; here are maelstroms in miniature, and tempests 

 in far less than a teapot ; rival and interfering currents 

 are whirling round and round, and making series of 

 concentric circles among the granules. Surely here is 

 material for our study. 



I see an object slowly creeping along the glass, 

 which will be just the thing for our purpose. It is the 

 Proteus (Aino&ba diffluens). Let me put on a higher 

 power, and submit it to your observation. 



Ton see a flat area of clear jelly, of very irregular 

 form, with sinuosities and jutting points, like the out- 

 line of some island in a map. A great number of 

 minute blackish granules and vesicles occupy the cen- 

 tral part, but the edges are clear and colourless. A 

 large bladder is seen near one side, which appears filled 

 with a subtile fluid. 



But while you gaze on it, yovi 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 outline is now presented. A great excava- 

 19 



