PROGRESSIVE POULTRY CULTURE 109 



must provide the best possible foundation for wise mat- 

 ing of his breeding stock and for the most successful 

 treatment of his fowls under whatsoever conditions he 

 may carry on the poultry business. 



DISSECTION, DESRCIPTION. 



The short, strong* somewhat curved beak of hard, 

 horny substance is well suited for seizing bits of food 

 or breaking into small pieces portions too large for 

 swallowing whole. Forcing open the bird's beak gives 

 one some idea of the strength of the muscles which 

 operate the lower mandible. This will also expose to 

 view the mouth and its parts. The arrow-shaped tongue 

 has its pointed part fitting neatly into the cavity of 

 the lower mandible, while its broader portion extends 

 back to the beginning of the throat By pressing a 

 finger up between the lower jaws from the outside, the 

 tongue may be pushed up showing its underside and 

 the muscle connected with its middle and rear portions. 

 Notice the difference in the surfaces of the upper and 

 under sides of the tongue. The roof of the mouth is 

 formed of tough cartilege which corresponds in size 

 and shape to the tongue but has a slit extending length- 

 wise along its middle. 



When food is taken into the bird's mouth there is a 

 slight flow of saliva through minute openings which 

 connect with thin glands in the sides of the mouth. 

 Grains, bits of grass or other green herbage, pieces of 

 meat and other food taken into the mouth are not 

 there mingled and masticated but are quickly swal- 

 lowed. The absence of teeth in the bird's mouth pre- 

 cludes the grinding of the food before it goes down the 

 food- tube 



By slitting open the mouth at the sides from the 

 juncture of the mandibles to the rear of the tongue all 

 the parts from the point of the beak to the beginning 

 of the gullet may be yery completely exposed for ex- 

 amination. 



Next looking down the gullet, just x below the base 

 of the tongue, a peculiar opening Is seen which is the 



