THE DUCK. 289 



Then these whalebones appear to answer much the same 

 purpose to the whale as the serrated or toothed bill does to 

 the duck. 



FREDERICK. 



What is that ? 



ESTHER. 



Ducks, and, I believe, most birds which live by suction, 

 have the inside of their heads, towards the edge, thickly set 

 with rows of short, strong 1 , sharp-pointed prickles. These 

 form a kind of filter; the liquid substances into which the 

 duck plunges her bill she draws, by the action of her lungs, 

 through the narrow interstices which lie between these teeth, 

 catching, as the stream passes across her beak, whatever it 

 may happen to bring along with it that proves agreeable to 

 her choice, and easily dismissing the rest.* 



HENRIETTA. 



Are there many whalebones in the mouth of a whale? 



MRS. F. 



The number varies from eight to nine hundred. I saw the 

 skeleton of the whale to which Henrietta alludes, and that 

 had eight hundred. This whale is supposed to have died of 

 old age, for the cartilages of the fingers of its fins were quite 

 ossified. 



HENRIETTA. 



Then how long is a whale supposed to live? 



MRS. F. 



A thousand years, according to the estimation of Buflfon 

 and Lacepede; and I have understood that Cuvier assigned 

 from nine hundred to a thousand to the one in question. It 

 is calculated that a pair of whales may live to count not less 

 that 72,000,000,000 of their offspring. 



* Paley. 

 25 



