66 
THE COMMON AMERICAN PARTRIDGE. 
voluted. They are marked with oblique-branched ridges on the inner sur- 
face. The intestine at this part is 2 twelfths in width ; the rectum, a b. 2 h 
twelfths, without cloacal enlargement. 
The trachea is 3 inches 2 twelfths Tong, flattened ; its breadth at the top 2 
twelfths, at the lower part 1 twelfth ; its rings cartilaginous, about 85 ; the 
lower very large, with a membrane intervening between its two portions. 
The lateral muscles are strong, but there are.no -inferior laryngeal muscles. 
The rings of the bronchi are only 10. 
Fig. 1 Fig. 2. 
