SEA-URCHINS AND SEA-CUCUMBERS 313 



CHAPTER XYI 



SEA-URCHINS AND SEA-CUCUMBERS 



PEERING- about among the rocks to-day at low tide, 

 I found, on turning over a large stone, an object 

 which, though familiar enough to those who are 

 conversant with the sea arid its treasures, would surprise 

 a curious observer fresh from the fields of Warwickshire. 

 It is a ball, perfectly circular and nearly globular only 

 that its under part is a little flattened hard and shelly 

 in its exterior, which is, however, densely clothed with a 

 forest of shelly spines, each one of which has a limited 

 amount of mobility on its base. On attempting to remove 

 it, I find that it adheres to the stone with some firmness, 

 and that on the exercise of sufficient force it conies away 

 with a feeling as if something were torn, and I find that 

 a multitude of little fleshy points are left on the stone. 

 Having dropped my prize into a glass collecting- jar of 

 sea-water, I presently see that it is slowly marching up 

 the side, sprawling out on every side a multitude of trans- 

 parent hands, with which it seems to feel its way, and 

 which are evidently feet also, for on these it crawls along 

 at its own tortoise-pace. And I now see that it is the 

 knobbed ends of some of these feet which were torn away 

 by my forcible act of ejectment, , and left clinging to the 

 stone. 



It was not the first time that I had seen the Sea-urchin 



15 SCIENCE 14 



