552 



VOLITATOIIES. GLIDERS. 



terially from those of the Excursores and Cantatores ; and 

 their trachea is furnished with inferior laryngeal muscles, 

 which gives them the power of uttering modulated sounds. 



The Cypselince, or Swifts, differ little in external appearance 

 from the Swallows ; but have the toes all directed forwards, 

 and the third toe exceeding the lateral less than in any other 

 group. Their wings are extremely long and narrow ; their 

 tail even or emarginate. Their digestive organs differ, inas- 

 much as the coeca, which are very small in the Swallows, are 

 in them entirely wanting. The inferior larynx is destitute of 

 muscles, as in the next group. 



The Caprimulgino}, or Goatsuckers, have the mouth exces- 

 sively wide, but the horny part of the bill generally very small ; 

 the eyes and ears very large ; the feet feeble, like those of the 

 Swallows ; the wings very long, but broad, and the tail elon- 

 gated. The gullet and stomach are very wide and thin, and 

 the intestines are furnished with large oblong coeca, like those 

 of the Owls, to which they are also allied in the texture of their 

 plumage, and their nocturnal habits. 



Fig. 263 represents the wing of a Swallow ; Fig. 264 that 

 of a Swift ; and 265 that of a Goatsucker. 



Fxo.265. 



