SWIFTS. 



439 



mucus, when separated out, gave some reactions different to a certain extent from 

 those which are given by ordinary mucin; but these differences were not great 

 enough to weaken the conclusion that the nest is really composed of mucus secreted 

 by the peculiar glands superficially described by Sir Everard Home as present in the 

 bird which builds the nest." 



Another group of this same sub-family have the tail-feathers rigid ; and in some, 

 as, for instance, our common chimney-swift (Chcetura pelagicd), the ends of the 

 shafts protrude beyond the end of the rectrices as so many spines. I need not dwell 

 on the well-known facts of the change of habits in these birds since the white man 

 took possession of this continent : how they in a great measure gave up the hollow 

 trees as roosting and nesting places, choosing his sooty chimneys as more accessible 

 and possibly more convenient, though to me personally it was a novel sight when a 

 few years ago a good friend of mine on a pleasant evening took me out in the country 

 to an old brick-yard, where hundreds of swifts circled around the high chimney, one 

 after the other dropping into the opening, as may-flies into an electric lamp. The 

 chimney-swift, or chimney-swallow, as it is often, but erroneously, called, is, like all 

 swifts in temperate climates, a regular migrant, which passes the winter in Mexico. 

 There is, therefore, no necessity for supposing " that it hibernates in hollow trees," or 

 in the mud beneath ponds, as is often asserted. Swallows and swifts may occasionally 

 be found in a torpid state, but the same is the case with all other kinds of birds, and 

 even with man, for that matter; but from such an occasional, exceptional, and proba- 

 bly pathological case to conclude that the swiftest birds on the wing, which with the 

 greatest ease in a few days can travel from the Arctic circle to a tropical climate, 

 regularly hibernate in hollow trees " is preposterous," as an esteemed contemporary 

 has put it. Juridical evidence may perhaps be adduced to the effect that swallows 

 hibernate in the mud or on the bottom of lakes ; but how many hundred old women 

 have not been burned to death as witches on jui'idical evidence ! 

 Nor has anybody yet succeeded in inti-oducing the ghost into the 

 zoological system, although we might produce juridical evidence in 

 confirmation of his existence. 



Remarkable as is the nidification of the swiftlets and the chim- 

 ney-swifts, that of some of the true swifts (Micropodinae) is not 

 less wonderful. Messrs. Godman and Salvin describe the nest of 

 Panyptila sancti-hieronymi, which they discovered in Guatemala, 

 as composed entirely of the seeds of a plant, secured together and 

 hung from the under surface of an overhanging rock by the saliva 

 of the bird. The whole forms a tube two feet and two inches 

 long by about six inches in diameter. The entrance is through the 

 lower end of the tube, and the eggs are placed on a kind of shelf 

 at the top. About the middle of the tube, on the external side, is 

 a protruding eave, as if overvaulting an entrance ; but there is no 

 hole, and it has the appearance as if it was placed there on purpose in order to deceive 

 some enemy, such as a snake or lizard, to the attacks of which the parent bird or its 

 offspring would, during the time of incubation, be more exposed. A section of the 

 nest is given in the accompanying cut. 



The genus to which the foregoing species belongs have the first (hind) toe turned 

 inwards. In the typical, or, rather, most specialized swifts, Micropus (or Cypselus), it 

 is directed forwards like the other toes. Both birds represented in the accompany- 



FiG. 220. Section of 

 the nest of Panyptila 

 sancti-hieronymi. 



