VI TROCHILIDAE 427 



filiform at the tip or narrowed throughout. The secondaries 

 are only six, or rarely seven. The tail of ten feathers may he 

 long or short, hut differs profoundly in shape, texture, and colour ; 

 being for example cuneate in FJiaethornis and S]3]ienoj)roctus, 

 nearly square in Urosticte and Hylocharis, rounded in Adelomyia 

 and Polytmus, deeply forked in Sa2:)])ho, Leshia, and the four 

 genera next named, of which Prymnacantha has the outer pair 

 of rectrices very narrow and pointed, Loddigesia, S'pathura, and 

 Disclira spatulate. 



The very characteristic tongue consists of a double tube, 

 tapering and separating into two externally lacerated sheaths at 

 the tip, w'hich contain the extensile portion. The " horns " of 

 the hyoid apparatus are greatly elongated, and pass round and 

 over the back of the head, meeting near the top, and thence 

 stretching in an ample groove to terminate in front of the eyes. 

 This arrangement, analogous to that found in Woodpeckers, 

 allows the tongue to be suddenly protruded to a considerable 

 distance, and withdrawn again in an instant. The furcula is 

 U-shaped; the syrinx has one or two pairs of tracheo-bronchial 

 muscles ; the aftershaft is very small ; a crop is present ; while 

 down is absent from both nestlings and adults. 



Except in the "Hermits" (p. 435), the brilliant coloration 

 almost defies description, the most exquisite metallic ^ or jewel- 

 like hues glorifying a background of green, blue, or brown ; 

 while crests, ear-tufts, neck -frills, and pendent beards ending 

 in points or forks, add to the effect. Only among the Passerine 

 Sun-birds (Nectariniidae) of the Indian and Ethiopian Eegions 

 can a fitting parallel be found ; but these, though often 

 erroneously termed Humming-birds, have no connexion with our 

 New World group. Eulampis and Pteroplianes are exceptional in 

 not having dusky remiges. The females are usually sombre in 

 comparison, and lack the ornaments of their consorts, which are 

 said to be occasionally smaller. The statement that young 

 males have no distinctive plumage seems incorrect. 



These gems of Ornithology extend from the north to the 

 extreme south of America, the habits differing slightly with the 

 climate ; Selasj^thorus rtifus of the Western United States reaches 

 Mt. St. Elias in Alaska, Trochilus coluhris occurs in the east up 

 to lat. 57 'N., Uustejjhanus gcdcritus frequents Tierra del Euego 



^ These are produced by the prismatic surfaces of the feathers, of. pp. 3, 4. 



