62 THE ANGLER-NATUEALIST. 



are capable only of projecting backwards — shutting down 

 like the props of an umbrella upon pressure from in front 

 — it would not appear that they could impede the opera- 

 tion of swallowing, but that, on the contrary, they would 

 naturally rather assist it than otherwise — in the same way 

 that the ' beard ' of an ear of barley assists it in forcing 

 a way through the sleeve of a coat or other obstructed 

 passage. 



The effect of these back-action chevaux-de-frise is 

 curiously illustrated by a circumstance of not unfrequent 

 occurrence in Sweden. Large Perch swallow the baited 

 hooks of stationary night-lines, and then enormous Pike 

 gorge the hooked Perch in their turn. In this case, 

 though the Pike is seldom or never actually hooked, yet, 

 on the fisherman's drawing in his line, the Perch sets so 

 fast in his throat that he is unable to get rid of it, and 

 both are taken *. That the spines of the Perch are very 

 formidable weapons, of which they readily make use, is 

 proved by an instance recently witnessed in a stock-pond 

 near Weybridge, where one of these fish, of about half a 

 pound, attacked a Pike of the same weight, — the result 

 being that after a prolonged contest, carried on by both 

 combatants with great fury, the Pike was apparently either 

 killed or stunned, and lay motionless on the bottom, belly 

 uppermost. Mr. Francis informs me, however, that Perch 

 themselves certainly do not object to these spines, so far as 



* Gosse's Natural History. 



