MIGRATIONS. 12.3 



that contains that element; thus furnishing a 

 strong proof of what are called compensating con- 

 trivances ; neither of these fishes have legs, yet 

 the one can walk and the other leap without 

 them, by other means with which the Supreme 

 Intelligence has endowed it. I may here ob- 

 serve that the serrated bone, or first ray of the 

 pectoral fin, by the assistance of which the flat- 

 head appears to move, is found in other Siluri- 

 dans, which leads to a conjecture that these 

 may sometimes also move upon land. 



Another fish, 1 found by Daldorff, in Tranque- 

 bar, not only creeps upon the shore, but even 

 climbs the Fan palm 2 in pursuit of certain Crus- 

 taceans which form its food. The structure of 

 this fish peculiarly fits it for the exercise of this 

 remarkable instinct. Its body is lubricated with 

 slime which facilitates its progress over the bark, 

 and amongst its chinks ; its gill-covers are armed 

 with numerous spines, by which, used as hands, 

 it appears to suspend itself; turning its tail to 

 the left, and standing, as it were, on the little 

 spines of its anal fin, it endeavours to push itself 

 upwards by the expansion of its body, closing 

 at the same time its gill-covers, that they may 

 not prevent its progress ; then expanding them 

 again it reaches a higher point ; thus, and by 

 bending the spiny rays of its dorsal fins to right 

 and left, and fixing them in the bark, it con- 



1 Perca scandens. 2 Borassus flabelliformis . 



