( 419 ) 



AMERICAN SWIFT. 



Cypselus pelasgius, Temminck. 



PLATE CLVIII. Vol. II. p. 329. 



Dr TowNSEND confirms the statement of General Clark, by men- 

 tioning that this species inhabits the Rocky Mountains, and the Co- 

 lumbia River district, I have found it breeding in the Texas. It 

 does not visit the Fur Countries. 



A specimen in spirits measures to end of tail 4| inches, to end of 

 wings 6A, to end of claws 3^ ; extent of wings 12| ; wing from flexure 

 5i ; tail 2iij. 



The bill is extremely short, the gape-line much decurved, the nos- 

 trils oblong, 1 twelfth in length, directed obliquely inward, and having 

 a prominent soft margin. The mouth is extremely wide, 6^ twelfths 

 in breadth ; the tongue triangular, flattened, 4 twelfths long, thin, pa- 

 pillate at the base, horny towards the end, and pointed. There is on 

 each side an oblong flattened salivary gland, lying between the branch 

 of the lower jaw and the mucous membrane of the mouth, into which it 

 opens near the junction of the crura, apparently by several ducts. The 

 oesophagus is 1 inch 9 twelfths long, of the uniform width of 2 twelfths. 

 The stomach is oblong, moderately muscular, 6^ twelfths long, 4| 

 twelfths broad ; its epithelium dense, reddish-brown, with twelve lon- 

 gitudinal rugcTe. The proventricular glands form a belt 4 twelfths in 

 breadth. The intestine is short and rather wide, 4| inches long, from 

 1| twelfths to 1 twelfth in breadth ; the rectum wider ; there are no 

 cceca ; the cloaca oblong. The lobes of the liver are about equal, the 

 left being 7| twelfths in length, the right 8 twelfths. 



The trachea is 1 inch 5 twelfths long, from 1 inch ^ twelfth to | 

 twelfth in breadth, flattened ; its rings extremely feeble, 58 in num- 

 ber, with 2 dimidiate rings. The lateral muscles are slender, as are the 

 sterno-tracheales ; a slender slip extends to near the last ring, but there 

 are no inferior laryngeal muscles. The bronchi are moderate, of about 

 12 half rings. 



The feet are extremely short, the anterior toes almost equal, the 

 hind toe very short, and capable of being directed forward. Although 



