MOCKING BIRD. 439 



The right lobe of the liver is very large, being 1 inch 1| twelfth in 

 length, and extending under the anterior part of the stomach, in the form 

 of a thin-edged rounded lobe ; the left lobe is 10 twelfths long, and lies 

 under the proventriculus and left side of the stomach. The heart is 

 of moderate size, 7^ twelfths long, 5 twelfths in breadth, of a conical 

 obtuse form. 



The aperture of the glottis is 1^ twelfth long, and furnished with the 

 same muscles as the other singing birds, viz. the thyro-arytenoideus, which 

 passes from the edge of the thyroid cartilage at its lower part to be in- 

 serted into the tip and sides of the arytenoid cartilage ; the thyro-cri- 

 coideus, which passes from the anterior edge of the thyroid backward to 

 the cricoid ; a small muscle, the crico-arytenoideus, which assists in clos- 

 ing the glottis ; and several small slips similar to those observed in 

 other Thrushes, and especially in the Crows, in which the parts, being 

 larger, are more easily seen. The trachea is 1 inch 10 twelfths in length, 

 considerably flattened, gradually tapering from 1^ twelfth to 1 twelfth ; 

 the rings, which are firm, are about 60, and 2 dimidiate rings. The 

 lateral muscles are slender, as are the sterno-tracheal. There are foiu* 

 pairs of inferior laryngeal muscles ; an anterior, going to the tip of the 

 first half-ring, another to the tip of the second, a third broader and in- 

 serted into a portion of the last half ring, the fourth or posterior or up- 

 per, long, narrow, and inserted into the point of the same half ring. 

 Besides these, as in all the land-birds, there is a pair of very slender 

 muscles, the deido-tracheal, arising from the sides of the thyroid car- 

 tilage and inserted into the furcula. The bronchi are rather wide and 

 short, of 12 cartilaginous half rings. 



As in all the birds of this family, there is a very slender salivary 

 gland on each side, lying between the branch of the lower jaw and the 

 mucous membrane of the mouth, upon which latter it opens anteriorly 

 to the frenum of the tongue. 



This species is abimdant in the Texas, where it breeds. The eggs 

 are generally one inch in length, and nine-twelfths and a quarter in 

 breadth. 



