46 MYRMOTHERINiE. 



The bill is uot essentially different from tliat of the Thrushes 

 and Orioles, being moderately stout, shorter than the head, 

 straight, with the dorsal outline couyexo-declinate, the tip nar- 

 row, the edges direct, and the upper mandible slightly notched. 

 The eyes and ears are of moderate size. The feet are rather 

 long and stout ; the tarsus compressed ; the toes of moderate 

 size, the first stouter and nearly as long as the second, which 

 is a little shorter than the fourth, the third much longer, and 

 united to the fourth at the base ; the claws moderate, arched, 

 compressed, laterally grooved, and in old birds rather blunt 

 from being worn. 



The wings are short, broad, concave, and rounded ; the quills 

 nineteen ; the first primary very short and narrow, the second 

 and third longest ; the secondaries long. The tail is always 

 short, sometimes extremely abbreviated ; convex above, even 

 or rounded, and composed of twelve rather broad rounded 

 feathers. The plumage is various, generally full and soft, its 

 colours often brilliant, at other times dull, so that no general 

 character can be derived from it. 



The skeleton of these birds probably differs in no very appre- 

 ciable degree from that of the Turdinre or Thremmaphilince ; 

 but as I have not examined that of any other species than our 

 Dipper, which is precisely intermediate between the Turdinfe 

 and the other Myrmotherinne, and therefore not " tA'pical," 

 I am not qualified to speak on this point. The skeleton of the 

 Dipper may be described in the same terms as those of the 

 Turdinoe generally. The cranium is of moderate size, ovate ; 

 the septum of the orbits incomplete : the jaws slender, the 

 upper with the nasal vacuity elliptical, the lower with an oblong 

 vacuity near the condyle. There are twelve cervical, eight 

 dorsal, ten united lumbar and sacral, and seven caudal vertebrae. 

 The ribs are seven, very slender and depressed. The scapula 

 is linear and slightly decurved ; the furcula narrow, its curve 

 rounded, and having a roundish thin plate projecting back- 

 wards ; the coracoid bones rather slender. The sternum is of 

 moderate length, broad, anteriorly narrower ; its posterior mar- 

 gin broad and nearly straight ; its anterior median process long 

 and furcate. The humerus is short ; the cubital bones a fourth 

 longer ; those of the hand of the same length as the cubitus. 



