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feet, 9. In their tails. 10. In their pectoral muscles, 

 which ara the strongest of all ; whereas in man, the 

 crural muscles are the strongest. 11. In the brain, as 

 Was before observed. 12. In the bronchia, which ex- 

 tends to the very bottom of the abdomen, so as to 

 contain a large quantity of air. 13. In the ovaries, 

 which in birds are single, and fastened on their back* 



4. The ears of birds differ much from those both of 

 men and beasts. There is almost a direct passage from 

 ear to ear, so that if the drum be pricked in either ear, 

 water poured in at one ear will run out at the other ; 

 and what is still more remarkable, they have a small 

 winding passage that opens into a large cavity, running 

 betwixt two skulls, and passes all round the head : the 

 upper of these skulls is supported by many hundreds of 

 small, thread. like pillars, which have another use also, 

 to break their sound, and hinder its making a con* 

 fused echo. 



This passage between the two skulls is much larger 

 in singing-birds than in others. So that a person who 

 has been shewn this may hereby know them from all 

 others. 



The other organs of sense are nearly the same in 

 birds as in other animals. Only there is a difference in 

 the organ of smell : the nostrils lie on each side of the 

 beak, in the inner part whereof, beside the tube which 

 reaches to the lungs there arc little tubes continued 

 from the membranes and substance of the brain, and 

 these seem to be the organ of smell. Only two nerves 

 pass through the os cribrosum to the beak, lest if there 

 were more perforations, as in other animals, too much 

 air might flow into the brain. 



The bill of-birds is peculiarly remarkable. In 

 the first place, it is neatly shaped for piercing the air. 

 In the next it is hard and horny, to supply the want 

 of teeth, and also in some measure, of a hand. Its 

 hooked form is of great use to rapacious birds, in 



