130 INSESSORES. CAPRIMULGUS. 



ing power of flight, and, as in the Swallows, their prey (con- 

 sisting of Phalgenae and other insects) is taken entirely upon 

 wing. In the aberrant forms the wings become much shorter 

 and rounded, and the bill acquires greater size and strength, 

 most displayed in the before mentioned genus Podargus. 

 In some the tarsi also become elongated ; and according to 

 these differences of structure a corresponding variation is 

 wrought in their economy. In Britain we only possess a 

 single species of the typical genus Caprimulgus ; the mem- 

 bers of the other genera ( Egotheles, Podargus, &c.), being 

 natives of the warmer climates of Asia, Africa, and America. 



Genus CAPRIMULGUS, Linn. GOATSUCKER. 



GENERIC CHARACTERS. 



Bill very short, weak, curved at the tip, broad and de- 

 pressed at the base; the upper mandible deflected at the 

 point. Gape very large, and extending as far as, or beyond, 

 the posterior angle of the eyes. The basal edge of the up- 

 per mandible bordered with strong moveable bristles directed 

 forwards. Nostrils basal, tubular, or with a large prominent 

 rim, clothed with very small feathers. Wings long, the first 

 quill shorter than the second, which is the longest of all. 

 Tail rounded or forked, of ten feathers. Feet having the tarsi 

 short, toes three before and one behind, the anterior ones 

 united as far as the first joint by a membrane ; the claw of 

 the middle toe broad, and serrated on the inner edge. 



The members of this curious genus are nocturnal and cre- 

 puscular feeders, and have, not unaptly, been termed Night 

 Swalloxcs. Here, however, the approach to the Strigidce is 

 not so conspicuous, as it is seen in the great curvature and 

 horny mass of bill of the genus Podargus, belonging to this 

 family ; which also possesses to a certain extent the radiating 



