OF FISHES. 65 



The pond was fished every seven years, and suppos- 

 ing that store pike of six or seven pound weight were 

 left in it, the growth of the pike in question must have 

 been at the rate of at least four pounds a year. Sal- 

 mon, however, grow much faster. It is now ascer- 

 tained that grilse, or young salmon, of from two 

 and a half, to three pounds weight, which are sent 

 to London markets in the month of May, come 

 from spawn only deposited in the preceding Octo- 

 ber or November, and the ova takes three months 

 of the time to quicken. It has also been ascer- 

 tained by experiment, that a grilse which weighed 

 six pounds in February, after spawning, has, on its 

 return from the sea in September, weighed thirteen 

 pounds ; and a salmon fry of April, will in June 

 weigh four pounds, and in August, six pounds. 



BRAIN BONES. 



Contiguous to the lobes of the brain, natural- 

 ists 'have discovered two peculiar bones, in com- 

 mon parlance, called 'brain bones. They are ena- 

 melled, like the finest tooth ; convexed on one 

 side, concave on the other, and serrated at the 

 edges. By cooks, these bones are termed thejish 

 money. By boiling, they are easily detached. In 

 looking into the cavity in which they are lodged, it 

 is evident that the fibres of the acoustic nerve ran 

 5 



