FOSSIL SPONGES, ETC. 9 



solid bodies, called fibres and spicules. The latter 

 arc of a variety of shapes, from the most simple to 



Fig. 5. Fig. 6. 



Fig. 7. 



Fig. 8. Fig. 9. 



F'gs. 5-9.— Fossil Sponge Spicules, from Elackdown and Haldon, all drawn on the 

 scale of ji'ith to is'oo'h of an inch, (After H. J. Carter.) 



the most complex, but they are interwoven so closely 

 together that when the sponge is dead and its "flesh" 



