4 MARVELS OF FISH LIFE 
As the dace approaches, the agitation of the pike 
increases, and though the body still shows no move- 
ment, the suppressed excitement of the pike is clearly 
seen by the further movements of the fin on his back, 
for the hindmost rays of this fin are swished from side 
to side, or the whole fin is rapidly opened and closed 
like a lady’s fan. 
At last the pike decides to attack, and immediately 
he takes up an attitude which clearly shows his inten- 
tions. The muscles of the body contract, the line of 
the back in consequence becomes as straight as an 
arrow, and at the same time the pike raises himself 
up on his fins. 
This attitude of intended attack is invariably present, 
and it may be maintained for only a few seconds or for 
several minutes. 
Should the dace now disappear, the pike’s muscles 
will again relax, and the fin on the back will gradually 
sink down; but if the dace continues to cruise round 
and round, the pike, propelled by a screw-like movement 
of the fin at the end of his tail, will slowly glide forward 
and stealthily follow the movements of the little fish. 
If the dace becomes alarmed, the pike will stop and hang 
motionless in the water, rigid and quivering with excite- 
ment. As soon as the little fish shows by his move- 
ments that he is again at his ease, the pike continues 
his stealthy approach, and when he is within striking 
distance there is a sudden rush, and the dace is seized 
across the body. A swirl on the surfaee of the water is 
