140 VIGNETTES FROM INVISIBLE LIFE. 



matter, from which bright and glistening thorn - 

 like bodies are projected in irregular diffusion. The 

 entire body is thus seen bristling all over like the 

 skin of a hedge -hog. 



FIG. 24. Sponyilla JluviatiUis. 



These thorn-like bodies or spicules, as they are 

 termed appear so embedded in the tissue of the 

 Sponge as if intended to sustain, distend, and ex- 

 pand it for a specific purpose ; and now, as we look 

 more intently, a number of small irregular openings 

 or pores, are visible, into which currents of water, 

 carrying with them fine particles of dust-like 

 material, are gently flowing. 



