CURRENTS OF THE LIVING SPONGE. 31 



into view, I beheld, for the first time, the splendid 

 spectacle it presented, a living fountain vomiting 

 forth from a circular cavity an impetuous torrent of 

 fluid, and hurling along in rapid succession opaque 

 masses, which it strewed everywhere around. The 

 beauty and novelty of such a scene in the animal 

 kingdom long arrested my attention ; but after twenty- 

 five minutes of constant observation, I was obliged to 

 withdraw my eye, from fatigue, without having seen 

 the torrent for one instant change its direction, or 

 diminish in the slightest degree the rapidity of its 

 course. I continued to watch the same orifice, at 

 short intervals, for five hours, sometimes observing it 

 for a quarter of an hour at a time, but still the stream 

 roUed on with a constant and equable velocity. About 

 the end of this time, however, I observed the current 

 become perceptibly more languid, the opaque flocculi 

 which were thrown out with so much impetuosity at 

 the beginning were now propelled to a shorter distance 

 from the orifice, and fell to the bottom of the fluid 

 within the sphere of vision, and in one hour more the 

 current had entirely ceased. 



" On attempting to examine some of the larger flat 

 species, as the Spongia panicea and Spongia cristata, 

 in the same manner with the microscope, I found it 

 not so practicable. The dissection necessary to re- 

 duce them to a size suitable for examination under 

 that instrument, threw open their canals so much, as 

 to destroy their means of manifesting a concentrated 

 current. But a single papilla, torn from a Spongia 

 papillaris, or other spreading sponge which has the 

 papillae much elevated, shows distinctly this interest- 



