posed of the multitudinous free-swimming young 

 of Aurelia: a fact which I confirm at once with the 

 aid of a dipping-tube and the microscope. 



Under the magnification of a low-power lens, 

 the lively little larvae are apparently as long, but 

 not quite so broad as my thumb-nail ; actually they 

 are smaller than mustard seeds. Pear-like in form, 

 diaphanous, and tinted with the soft appealing 

 color of old rose, they swim across the field of the 

 microscope with their larger, or bulbous, ends fore- 

 most. They move in graceful curves, and so swiftly 

 do they go that it is difficult for the eye to follow 

 them. Only when I retard them with a narcotic or 

 by other artificial means am I able to determine 

 how the all but invisible motes propel themselves. 

 Like the downy bloom on blades of wildgrass, 

 there are then revealed innumerable crowded pro- 

 cesses, short tenuous cilia, completely investing 

 the surface of the semi-transparent bodies. The 

 rapidly-vibrating hairs are the machinery of loco- 

 motion. 



For several hours the young creatures continue 

 to hover on that side of the tanks which receives 

 the strongest light. They do not yet seem to as- 

 similate food. Nor does there appear to be any 



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