JELLY-FISHES. 355 



tkreads 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 delicate thread is not 

 simple, but is furnished along one side, throughout its 

 length, at regular distances, with a row of secondary 

 filaments, which project at right angles from the main 

 thread. 



These secondary filaments constitute an important 

 element in the charm which invests this brilliant little 

 creature. They are about fifty in number on each 

 thread, and some of them are half an inch long, when 

 fully extended, but it is seldom that we see them thus 

 straightened ; for they are ever assuming the most 

 elegant spiral coils, which open and close, extend and 

 contract, with an ever-changing vivacity. The animal 

 has a very perfect control over the threads, as well as 

 over the secondary filaments in their individuality. 

 One, or both, are frequently projected from their 

 chambers to their full extent by one impulse ; some- 

 times the extension is arrested at any stage, and then 

 proceeded with, or the thread is partially or entirely 

 retracted. Sometimes the secondary filaments are 

 coiled up into minute balls scarcely perceptible, or only 

 so as to give to the main thread the appearance of 

 small beads remotely strung on a fine hair ; then a few 

 uncoil and spread divergently ; contract again, and 

 again unfold ; or many, or all, interchange these actions 

 together, with beautiful regularity and rhythmical uni- 

 formity, repeating the alternation for many times in 

 rapid succession. 



The beauty and diversity of the forms assumed by 

 these elegant organs beguile us to watch them with 



