SPONGES. 



15 



In a large proportion of the Venus' s flower-baskets occurs a small crus- 

 tacean. It was formerly thought that the ingenious Chinese cut holes in 

 the sponge, inserted the shrimp, and then deftly concealed the traces of 



Fig. 14. — Venus's flower-basket sponge (Euplectella). 





the operation. It would appear, however, that the association is a normal 

 one, for we do not find that diversity in the enclosed shrimp which would 



