THE BEATING OF THE JACKS. 



115 



sence of color ; or perhaps a ray was approached, 

 which darted off with a bird-like motion of its 

 fins. It was a perfect panorama, every step offer- 

 ing some new and attractive form. 



" What are those round things, shells or 

 stones ? " asked Harry, as the boat passed over 



it f 



y 



B 



Diagram of the growth of a sea-squirt or ascidian. A a, Young free swim- 

 ming stage, a 2 , Intermediate stage when first settling down. B 6, 

 Full-grown sea-squirt, m, mouth ; e, hollow brain with eye ; ^, gill 

 slits ; A, heart ; r, rod of gristle in free swimming form ; nv, nerve cord 

 in same ; t, tail in process of absorption in intermediate form. 



some curious oval objects protruding from the 

 sand. " Hold on a minute," he added, and 



