THE ENGLISH SPARROW 85 



tongue, find the U-shaped liyoid bone surrounding the front 

 of the glottis. 



Respiratory organs. The glottis opens into the larynx, 

 a slightly swollen chamber. From the larynx, the trachea 

 extends posteriorly, until it branches into two small tubes, 

 the bronchi. At the union of the bronchi and trachea is a 

 swollen portion, the syrinx. It has cords stretched across 

 the inside. This is the song box of the bird. Trace the 

 bronchi to the lungs. Inflate the lungs through the glottis, 

 and note the large air sacs in the abdomen that are connected 

 with the lungs. 



In observing the lungs, the viscera had probably to be 

 pushed aside. Allow them to return to place. Note the 

 heart, with the large blood vessels leading from 'it. Do not 

 cut them yet. Dissect out and remove the trachea and 

 anterior ends of the bronchial tubes. 



Digestive organs. Note the gullet beneath the trachea. 

 In the middle of the gullet is an enlargement forming the 

 crop. Inflate the gullet to show the crop. The gullet, 

 after leaving the crop, soon enters the stomach, which is 

 difficult to find because it is scarcely larger than the gullet 

 itself. The stomach, however, ends at the gizzard, which 

 is a thick-walled organ for grinding the food. Find the 

 gizzard. The intestine starts from the posterior end of the 

 gizzard and immediately forms a loop which is known as 

 the duodenum. Within the loop forming the duodenum 

 is a pinkish gland, the pancreas. Behind the heart is the 

 large, brownish liver that empties its bile into the duo- 

 denum. The intestine is considerably widened at the pos- 

 terior end. This widened portion is the cloaca. On each 

 side of the intestine near the end is a blind sac. These 

 are called the cceca. 



