In swimming it propels itself upward with I'ytlimic pulsa- 

 tions of the bell-mar{;;in, t?ie tentacles shor-tened and the 

 bell very convex. ("Pig. 2) Upon reaching the surface the 

 creature keels over almost instan+ly, and floats slowly 

 downwards with bell relaxed and inverted, and the tentacles 

 extended far out horizontally, forming a wide expanse of 

 stinging threads, which carry certain destruction to animals 

 even larger than the jelly-fish itself, if they are unwary 

 enough to be caught within their reach. Gonionema contin- 

 ues this peculiar fishing up and down in the water with 

 little respite. Occasionally it fas+ens itself to the eel 

 grass or other object near the bottom, or stops midv/ay in 

 its course with tentacles extended as in my figure 1, well- 

 nigh invisible, but a deadly foe to small fish or crusta- 

 ceans, which cross its path. 



II. GONADS . 



In the mature Gonionema the sexual organs are 

 "frill-like lobes, passing from one side to the other of 

 the chimiferous canal". (Agassiz, 186b). Their form and 

 position is shown in figures 3 and 4. The free edge of the 

 ribbon of tissue is thickened and rounded, and is bent back- 

 wards and forwards across the radial canal. The color of 



