626 Marvels of the Universe 
Photo by) a iets [G. Rk. Balance. 
ICE FLOWERS. 
These splendid examples of the frost’s work were covering the rough surface of an old wall. Atmospheric conditions have 
been such and the air sufficiently still to allow the delicate petals to combine and form singularly perfect rosettes. 
By way of contrast, we have fishes which swim belly uppermost! A well-known instance 
of this kind of topsy-turvy locomotion is furnished by some of the Cat-fishes. One of these, 
a native of the Nile, was well known to the ancient Egyptians, and was frequently depicted 
swimming after its peculiar fashion on their wall-paintings. But associated with this strange 
manner of locomotion is a no less striking peculiarity of coloration ; for whereas, for protective 
purposes, in other fishes the back is much darker than the belly, in this fish the belly is darker than 
the back! Thereby, of course, the fish escapes the keen eyes of other predaceous fishes, for the 
dark upper surface (the belly) counteracts the effects of the strong light from above, while the 
white under surface (the back) neutralizes the blackness of the depths below. But locomotion in 
this case is performed, as in ordinary fishes, by side-to-side movements of the tail and tail fin. 
Only one other group of fishes contains members which swim belly uppermost. These are the 
Globe-fishes. Normally they swim after the typical fashion. But when alarmed the fish, rushing 
to the surface, suddenly inflates the abdomen and turns turtle. The globular belly now 
projecting above the surface of the water, is caught by the wind and borne along. Thus are enemies 
avoided 
partly by the dangerous armature of spines which stud the whole body, and partly by 
removal to a distant spot. 
As a rule, probably, most of us regard the breast fins in fishes as the rowing organs ; their use 
for this purpose is negligible. They serve as balancers and steering organs. But among the Skates 
the breast fins have been developed to form huge muscular wings, and these alone are concerned with 
locomotion, driving the body through the water by means of their peculiar wave-like undulations. 
