1 804 THE PICARIAN BIRDS 



differences from the rest of the swifts that they have been separated as a distinct 

 family. The plumage is much softer than in the majority of the swifts, and thus 

 shows an approach to that of the goatsuckers. The sexes are different in color, 

 and the young very distinct from the adults; whereas in the other swifts there is 

 very little difference between the plumage of the young and the old birds. The head 

 is generally crested, and some of the species have elongated whisker streaks of white. 

 The metatarsus is shorter than the third toe, which is not the case in other swifts, 

 while the hinder margin of the breastbone has two distinct perforations; in ad- 

 dition to which the nesting habits are quite peculiar. Writing on this subject, Mr. 

 K. Thompson observes that "it is not in the high or deep forest that the bird 

 breeds, but in scattered jungle, usually covering low .stony hills and ridges. The 

 nest in this particular case was in a tree quite by itself, with only a few others 

 in the neighborhood scattered about here and there. My attention was directed to 

 the male bird, who was trying his best to dislodge a dove from a tree near to the one 

 on which I ultimately found the nest. I knew that there must be a nest somewhere 

 near, and soon caught sight of the female sitting transversely across a thin dead 

 bough, the tiny nest, glued on to the side of this branch, being, as usual, scarcety 

 perceptible from below. I have seen two other nests of this swift in this neighbor- 

 hood, each containing a tolerably well-fledged young one. The nests in these in- 

 stances also were placed on Boswellia trees. To the best of my belief they never lay 

 more than one egg in the nest." Mr. Hume adds that " the stem to which the nest 

 was attached is about eight-tenths inch in diameter; against the side of this the 

 nest is glued, so that the upper margin of the nest is on a level with the upper sur- 

 face of the branch. The nest itself is half of a rather deep saucer, one and seventy- 

 five-hnndredths inches in diameter, and about six-tenths in depth internally. The 

 nest is entirely composed of thin flakes of bark, cemented together by the bird's 

 saliva, and is about an eighth of an inch in thickness. The egg is a very elongated 

 oval, obtuse at both ends, and with little or no gloss. It is white, with a slight 

 grayish-blue tinge, and measures ninety-four-hundredths in length by sixty-one- 

 hundredths in breadth." 



THE NIGHTJARS 

 Family CAPRIMULGID^R 



Ivike the swifts, these birds, have very wide and gaping mouths; while their 

 plumage is mottled and vermiculated, very much resembling that of the owls, near 

 which group they have been placed in many classifications. Beyond the resemblance 

 of their plumage, and the fact that they are crepuscular birds, coming out to hunt 

 for their prey in the twilight, there is, however, little in common between the two 

 groups; the former being birds of prey, devouring chiefly animal food and laying 

 white eggs, mostly in a concealed position in the hole of a tree; whereas the eggs of 

 the nightjars are laid in the open, and are more or less spotted and marked. The 

 number of both the primary quills and tail feathers in the nightjars is ten, the palate 



