JELLY-FISHES 349 



frolic and revel as if still in the enjoyment of unrestricted 

 liberty. And here they are. 



Among these bright and agile beings which are shoot- 

 ing their wayward traverses across each other, and inter- 

 twining their long thread-like tentacles, we will select one 

 or two for examination, as samples of their kindred. And 

 first let me isolate this active little Beroe (Gydippe pomi- 

 formis), which I dip out with a tea-spoon and transfer to 

 this other glass jar, that we may watch its form and move- 

 ments unaffected by the presence of its companions. 



We see, then, a little ball, almost perfectly globular, 

 except that a tiny wart marks one pole, of the size of a 

 small marble, and apparently turned out of pure glass, or 

 ice, or jelly according to your fancy perfect transpar- 

 ency and colorlessness being its characteristics, so much 

 that it is not always easy to catch sight of the little creat- 

 ure, except we allow the light to fall on the jar in a par- 

 ticular direction. From two opposite sides of the globe 

 proceed two threads of great length and extreme tenuity, 

 which display the most lively and varied movements. 



These filaments shall occupy us for a few moments. 

 We trace them to their origin, and find that they proceed 

 each from the interior of a lengthened chamber, on each 

 of two opposite sides of the animal. Suddenly, on the 

 slightest touch of some foreign object, one of the threads 

 is contracted to a point and concealed within its chamber, 

 but is presently darted forth again. When the lovely 

 globe chooses to remain still, the threads hang downward, 

 gradually lengthening more and more, till their extremities 

 lie along the bottom of the jar, extended to a length of 

 six inches from the chamber. Then we see that this deli- 

 cate thread is not simple, but is furnished along one side, 



