40 BERTHA'S VISIT TO HER 



told me that sponges, of which there are now 

 known more than a hundred different species, 

 are found in a multitude of places, on the shores 

 of both the old and new Continents. l( Those 

 most valued in the arts," said he, " are inhabi- 

 tants of the Mediterranean, and part of the 

 Indian Ocean ; two small kinds of sponge thrive 

 even on the frozen shores of Greenland ; and 

 forty species have been discovered on the coasts 

 of Great Britain. They are found equally in 

 places that are always covered by the sea, and 

 in those which it leaves dry with the ebb tide. 

 They adhere to rocks, and spread all over their 

 surface ; in some places they keep possession of 

 the most exposed cliffs, but they thrive best in 

 sheltered cavities, and are found lining the walls 

 of submarine caves, attaching themselves indif- 

 ferently to mineral or vegetable, or even to animal 

 substances. 



" The size to which sponge attains is very un- 

 certain ; I lately saw an account of one found at 

 Singapore in the East Indies, which was shaped 

 like a goblet, and measured round the brim fifty- 

 one inches ; the stem was seventeen inches, 

 and it contained thirty-six quarts of water ! Na- 

 turalists have agreed to seven general divisions 

 of form ; so as to make something like an ar- 

 rangement of this most singular class of organ- 

 ized beings." 



I interrupted my uncle here, to ask whether, in 



