100 



nest-building, plays just as important a part in the nourishment of the 

 young ? What yields such delicious soup for a Chinese mandarin 

 ought suiely to make good pap for a young swiftlet. Something analo- 

 gous to this is well known to take place in the pigeon family where the 

 nestlings are fed with a material disgorged from the crop of the parent 

 and consisting largely of a milky and nutricious fluid secreted by the 

 walls of the crop. 



In such works as treat of the swifts the subject of nourishment of 

 the young is touched but lighily, if at all, though some writers express 

 a suspicion — it is never stated positively — that they are in the habit 

 at this season of hawking during the night for insects to supply the 

 oi'ten recurring demands of the nestlings. It is true that the roaring of 

 wings in the chimney and the voices of both old and young birds are 

 to be heard several times every night ; but I believe this may be 

 accounted for by the movements of the parent birds m exchanging 

 places as they take turns in the care of the young. The mate generally 

 roosts at some little distance from the nest, and, as remarked before, 

 they always move either by actual flight or by a half flying, half-climbmg 

 movement which is sufficient to occasion all the noise that is heard. 

 Moreover, though bats and night-hawks are visible enough any summer 

 night, I do not know any record of a chimney swift having been seen 

 in pursuit of prey, eren by the brightest moonlight, after nine o'clock ; 

 and so far as my observations extend they seem to show greatest activity 

 and highest flight during the sunniest hours of the day. The presence 

 of the shade over the eye, too, seems to mark this bird as a lover of 

 sunshine rather than of dusk. 



The regular complement of eggs is from 4 to 6, but only three were 

 hatched out in this case. I'he young grew rapidly, however, and soon 

 filled the nest to overflowing. 



By the of 4th August the stiff tail feathers were plainly visible, and as 

 the young seemed to be crowding each other over the edge, I took a stick 

 and dislodged the nest, catching it and its contents on a cloth fastened 

 across the flue for that purpose. The little birds weie not at all injured 

 and started at once to climb up the side again, using claws, wings and 

 tail with much vigor. One taken out and kept in the room a few 

 minutes proved to oe about half fledged and \vzs in colour and mark- 



■r^. 



