142 THE WORLD OF THE SEA. 
foundations. Their colours are bright, and frequently they look 
as though they were made of porcelain. 
The species which is found on the coast of Ireland, the Cydippe 
pomiformia, is a little iridescent sphere of pure crystal. When they 
eat, the prey may be watched traversing this transparent tissue. 
Their sides are fringed with semi-transparent and very mobile cilia, 
by whose aid these beautiful little balloons glide through the waters 
like meteors. The rows of cilia move alternately, one resting while 
the other is in motion. The movements of this beroe are very 
capricious ; sometimes it rises gently to the surface of the water, 
like a slowly-ascending bubble, and then it descends again as 
slowly ; another time it comes up rapidly, and falls again like a 
stone into the depths. At another time it remains quite stationary, 
and turns round on its vertical axis, so making a number of pro- 
gressing circles, like an elegant dancer. 
This pretty creature is furnished with two very fine and delicate 
tentacles, six times longer than its body. They are flexible 
capillary tubes, which have lateral branches, short and arborescent. 
These tentacles descend from the under part of the creature, and 
diverge from each other; they are very wavy, and are not unlike 
spiders’ threads. We are told that their surface is covered with 
Microscopic vesicles, straight and upright, by which, probably, 
they either stupify their prey, or hold it fast. The weakest organ 
has always something to compensate for its weakness, and here a 
fine and almost imperceptible thread is a very dangerous weapon. 
It appears that the beroe is phosphorescent; when disturbed it 
produces a light which appears like a luminous twisted column, 
continually changing its place, because of the gyratory motion in 
which the animal indulges. 
The Velelle have an interior cartilage, which is oval and trans- 
parent, and gives consistency to the gelatinous substance of their 
body. This animal, shown in the accompanying figure, is like 
an umbrella in shape; its colour is of a dark blue, furnished on 
its under surface with a number of suckers, and a vertical tuft, 
like a sail fixed to its cartilage, crosses its back obliquely. The 
velelle often float on the waves in great numbers, covering the 
waters with what look like little flowers, which the zephyrs, as they 
breathe, gently waft before them. 
