DISCOPHORA. 77 



that the entire group of the Discophora will have to be ulti- 

 mately done away with. 



The naked-eyed Medusae are all exceedingly elegant and 

 attractive, when examined in a living condition, resembling 

 little, bells of the most transparent glass, adorned here and 

 there with the most brilliant colors. They occur, in their 

 proper localities and at proper seasons, in enormous numbers, 

 and they constitute one of the staple articles of diet to the 

 Greenland whale. They are mostly phosphorescent, or capa- 

 ble of giving out light at night, and they appear to be one of 

 the principal sources of the luminosity of the sea. It does not 

 seem, however, that they phosphoresce unless disturbed or 

 irritated in some way. 



