280 POPULAR HISTORY OF THE AQUARIUM. 



matter of which it was composed ; at other times they would 

 carry to it, in their moaths, fine conferva-stems, and press 

 them with considerable force into the walls of the nest, or 

 thrust thetn into the hole, which by this means was partially 

 concealed. 



" Occasionally, each was observed hovering over its nest, 

 with the head close to the orifice, the body being inclined 

 upwards at an angle of about forty-five degrees, fanning it 

 with the pectoral fins, aided by a lateral motion of the tail. 

 This curious manoeuvre was apparently, so to speak, for the 

 purpose of ventilating the spawn, which would be distinctly 

 seen through the orifice at the top; at least by this means 

 a current of water was made to set in towards the nest, as 

 was rendered perfectly apparent by the agitation among 

 the particles of matter attached to it. This fanning or ven- 

 tilating process was repeated at short intervals during the 

 day, and every day until the spawn was hatched, to accom- 

 plish which, took between two or three weeks. 



Only one nest contained spawn ; the other was torn in 

 pieces, and the materials scattered about, in the hope that 

 we might have the pleasure of seeing it reconstructed. In 

 this we were not disappointed ; the fish immediately began 

 to form a new nest in exactly the same spot, and by the 



