364 



EVENINGS AT THE MICEOSCOPE. 



fying power which yoa are at present using, that a 

 clear fluid is moving rapidly within all these canals, 

 carrying minute granules ; not with an even forward 

 current, but with an irregular j erking vacillating move- 

 ment, as if several conflicting eddies were in the stream. 

 Yet we discern that, on the whole, the granules 

 are moved forward; passing 

 from the centre of radiation 

 towards the margin, when we 

 see them slip into the marginal 

 canal from the several mouths 

 of the radiating canals. 



This is a very simple and rudi- 

 mentary blood-system. There 

 is here no heart with its pulsa- 

 tions, no proper arteries or veins', 

 no lungs for oxygenation ; but 

 the products of digestion are 

 themselves thus circulated 

 through the system. And this 

 brings me back to the central 

 point, whence you see depend- 

 ing the curious organ I spoke 

 of. A long cylinder of highly 

 moveable and evidently sensi- 

 tive flesh hangs down from the 

 middle of the roof exactly like 

 BinsiA. ^j^g clapper of a bell; and, as 



if to add to the resemblance, this same clapper is sus- 

 pended by a narrow cord, and is terminated by a knob. 

 Sometimes this whole organ is allowed to hang 

 about as low as the edge of the bell ; then it gradually 

 lengthens to twice, thrice^ nay to five times that 



