28 TROCQILI. 



beyond which they become flattened, concave above, thin-edged and 

 lacerated externally, thick-edged internally, and though lying 

 parallel to one another and in contact can be separated. 



The trachea bifurcates very high up, there being a small globular 

 swelling at the fork *. There are no sterno-trachiales muscles. 



The heart is very large, and the left carotid artery runs in a 

 direct course. 



The inteMinal canal is entirely covered by the liver. There are 

 no caeca. 



Pterijloijraphii t. — A median naked space of a spindle-shaped 

 outline on the crown, running longitudinally between the eyes and 

 the base of the maxilla ; median naked space of the neck continued 

 nearly to the base of the mandible ; a large naked nape-space ; the 

 humeral tract passes over the head of the humerus, and the femoral 

 tract is apparently absent ; the spinal tract is very broad and 

 iozenge-shaped, spreading over nearly the whole of the dorsal 

 region ; a short longitudinal naked strip occupies tlie middle of this 

 tract. 



The number of rectrices is 10, of primaries 10, secondaries 6. 



The wings generally are very uniform in structure, but in some 

 species the outer primary is filiform towards the tip, and in others 

 narrow for the whole of its length. 



The tail is very diverse in form, and in some cases, as in Loddi- 

 ffcsia, profoundly modified. 



The plumage generally, especially on the upper surface, has 

 shining quasi-metallic tints, and special effects are produced, chiefly 

 on the crown and throat, by glittering squamosa feathers. 



The female builds a cup-shaped nest, of varied material, such as 

 moss, &c., the exterior of which is frequently covered with spiders' 

 web and ornamented with small bits of lichen. These are stuck on 

 to the outside. The eggs are always two in number, rather elongate 

 in form, and rounded nearly alike at each end ; their colour is 

 always white. 



The Trochili may be divided into three sections, as follows : — 



Section A. — Sheath of the maxilla serrate towards the I Trochili 

 anterior portion of the tomia ; the sheath of the > serrirostres, 

 mandible sometimes similarly serrate ) p. 20. 



Section B. — Sheath of the maxilla indistinctly and | intermedii 

 feebly serrate towards the end of the tomia | .i 114 ' 



Section C. — Sheath of both maxilla and mandible | igevirostres 

 with a smooth tomia to the end f q^q ' 



* ShufekU, Journ. Linn. Soc, Zaol. xx. p. oSi), pi. '2o. 

 t Id. ibid. p. 1566. 



