GRINDERS AND SOLVENTS 93 



particularly strong, and in some cases even provided 

 with gristly or bony crushing-discs, in order to 

 triturate nuts or the stones of fruit. 



The strong gizzard of Fowls and Ducks is also 

 well known ; that of the Turkey is so powerful 

 that in the experiments of Spallanzani, who more 

 than a century ago conducted experiments without 

 any regard for humanity but with unimpeachable 

 accuracy, a leaden ball studded with small lancets 

 was found after eighteen hours with its armature 

 destroyed, while the gizzard was discovered quite 

 uninj ured, when the Turkey was killed. And among 

 the Ducks the shells of the hard molluscs and 

 crustaceans that such sea-haunting forms as the 

 Eider-duck feed upon are speedily reduced by the 

 action of the gizzard to a substance resembling sand. 

 No doubt the gastric juice has something to say 

 in this result as well as the extraordinary power of 

 the muscular contractions of the stomach ; for some 

 birds with soft stomachs can do wonders in the way 

 of reducing hard substances, such as bone. 



I have, for instance, given to the Goosander 

 {Merganser castor), a fish-eating Duck with a soft 

 stomach like a bird of prey, no less than forty fish 

 about the size of small sprats, at a meal, just to see 

 how many he could take ; and there showed no 

 signs of bone in the droppings that were passed. 

 I had a similar experience with another fish-eater, 

 the Indian Dwarf Cormorant (Phalacrocorax java- 

 nieus), which also digests fish bones and all ; a half- 

 fledged young Indian Swift (fiyfselus a-ffi/nis) given 



