

Fig. 72. HiritniJu crythropyyia. 



Family HIRUNDINID^E. 



The intrinsic muscles of the syrinx fixed to the ends of the 

 bronchial semi-rings ; the edges of both mandibles perfectly 

 smooth, with a single notch or the indication of one in the upper ; 

 the hinder part of the tarsus longitudinally bilaminated, the 

 laminae entire and smooth ; wing with nine primaries, the first and 

 second nearly equal ; bill Hat, broad and triangular when viewed 

 from above ; gape very wide ; the longest secondaries reaching to 

 about the middle of the wing ; front of tarsus smooth ; rectrices 

 twelve: sexes alike; a moult in the spring only; young very 

 similar to the adult ; rictal bristles weak. 



The Swallows form n well-defined group of birds remarkable for 

 their great powers of flight, the whole of their food, which consists 

 of small insects, being caught on tin- \\ ing. Many of the Swallows 

 migrate vast distances, others are resident, and some species are 

 confined to small areas. 



