166 The Under-Water World 



sharp spines which act as climbing irons. 

 It is noteworthy that climbing perch are 

 wanderers by necessity rather than by 

 inclination, those at the Zoo Aquarium, 

 though provided with tempting tree 

 trunks, never evincing the slightest desire 

 to leave the peace and plenty of the 

 waters. 



Eels are given to " walking," or rather 

 wriggling, and the fact that they are 

 found in Swiss lakes thousands of feet 

 above sea-level, implies that they possess 

 very considerable powers of endurance 

 out of water. 



A number of fishes which cannot be 

 altogether classed as parasites obtain 

 their food by acting as hangers on or 

 camp followers to more active forms. A 

 case in point is that of the Remora or 

 Shark-sucker, which carries a large oval 

 sucking plate on its head. By means of 

 this disc it attaches itself to the under 

 surfaces of sharks and turtles, sharing in 



