342 NATURAL HISTORY, 
of its prey. These tentacula carry the food to the mouth. 
The stinging power possessed by them is probably of 
service in overcoming its prey, like the poison of the 
Scorpions and other insects. At A you see the under 
surface, showing the mouth in the middle. The resem- 
blance in arrangement to the Actiniz is very obvious, 
the chief difference being that, in the one group, the 
mouth is above, while in the other it is on the under sur- 
face. The Medusz often reach a considerable size. It 
is said that they have been seen of three or four feet in 
diameter, and of even sixty pounds weight. Although 
they are such watery animals, they eat solid food, for in 
their stomachs have been found small Crustacea, Mol- 
lusks, and even Fishes. 
596. The Acalephs generally float near the surface of 
the water, and sometimes are seen in great abundance 
basking in the sun, and reflecting its rays in such a man- 
ner as to make a play of the most brilliant colors. The 
phosphorescence sometimes seen in the sea is owing 
chiefly to small Acalephz. Carpenter thus describes the 
beauty of this phenomenon as witnessed in the warmer 
latitudes: ‘“‘The whole surface of the ocean displays a 
diffused luminosity, like that of the Milky Way on a clear 
night. ‘The path ofthe ship is marked by a brilliant line 
of glowing light. The waves, as they gently curl over 
one another (this phenomenon is never seen with a rough 
sea), break into brilliant spangles. The oars of a boat 
rowing over them seem dripping with pearls when raised 
from the water, and every stroke is marked with a new 
line of brightness. And amid this general splendor, va- 
ried forms of more glowing lustre are seen to move— 
some like ribbons of flame, some like globes of fire, some 
gently gliding through the still ocean, others more rap- 
idly moving just beneath its surface.” 
597. To the Ciliograde order of Acalephs belongs the 
common Beroe, Fig. 269, which is thus described by Dr. 
Harvey, an English naturalist: ‘This little creature is 
