150 OF INSTINCT. SICT. XVI. 4* 



motion. Thus the colt, and the lamb, are much 

 more perfect animals than the blind puppy, and the 

 naked rabbit ; and the chick of the pheafant, and 

 the partridge, has more perfect plumage, and more 

 perfect eyes, as well as greater aptitude to loco- 

 iriotion, than the callow neftlings of the dove, and 

 of the wren. The parents of the former only find 

 it neceffary to (hew them their food, and to teach 

 them to take it up ; whilft thofe of the latter are 

 obliged for many days to obtrude it into their gap- 

 ing mouths. 



IV. From the facts mentioned in No. a. of this 

 Section, it is evinced that the foetus learns to fwal- 

 iow before its nativity ; for it is feen to open its 

 mouth, and its ftomach is found filled with the 

 liquid that furrounds it. It opens its mouth, 

 either infligated by hunger, or by the irkfomenefs 

 of a continued attitude of the mufcles of its face ; 

 the liquor amnii, in which it fwims, is agreeable 

 to its palate, as it coniifts of a nourifhing material, 

 (Haller Phyf. T. 8. p. 204;. It is tempted to ex- 

 perlence its tafte further in the mouth, and by a few 

 efforts learns to fwallow, in the fame manner as we 

 learn all other animal actions, which are attended 

 with confcioufnefs, by the repeated efforts of our 

 mufcles under the condutt of our fenfatlons or voli- 

 tions. 



The infpiration of air into the lungs is fo totally 

 different from that of fwallowing a fluid in which 

 \ve are immerfed, that it cannot be acquired be- 

 fore oar nativity. But at this time, when the 

 circulation of the blood is no longer continued 

 through the placenta, that fuffocating fenfation, 

 which we feel about the precordia, when we are 

 in want of frefli air, difagreeably affects the infant : 



and 



