— ere 
CAPRIMULGID. 307 
Family CAPRIMULGIDE, or NIGHTJARS. 
The Nightjars or Goatsuckers are a group of birds bearing a remarkable 
family likeness, but divisible into two subfamilies, the Caprimulgine and 
the Podarginz, which are placed by Sclater in different suborders. In the 
former, the claw of the middle toe is pectinated, the outer toe is composed 
of only four phalanges, and the sternum has only one notch on each side of 
the posterior margin. In the latter, the claw of the middle toe is not pecti- 
nated, the outer toe consists of five phalanges, and the sternum has two 
notches on each side of the posterior margin*. The Caprimulginz were 
associated by Forbes with the Bee-eaters, Rollers, and Owls, in juxtaposi- 
tion with the Passerine birds; but Sclater places them with the Swifts 
and the Humming-birds. 
Though they are associated by Huxley with the Swifts, the Wood- 
peckers, and the Passerine birds, this writer states that in many respects 
they present a marked contrast to these families in the modifications of 
their cranial bones. Nitzsch says that they very nearly approach the 
Swifts in their pterylosis ; but in their myology and digestive organs they 
are supposed to be most nearly allied to the Bee-eaters and Rollers. 
The Nightjars moult twice in the year, in spring and autumn. 
In their external characters they are intermediate between the Swifts, 
the Owls, and the Cuckoos, having the small bill and wide gape of the 
Swifts, the soft pencilled plumage of the Owls, and the long tail of the 
Cuckoos. The wing contains ten primaries, and there are only ten tail- 
* This character does not appear to be constant. Although the Caprimulgine are sup- 
posed to agree with the Passeride in having only one notch in the posterior margin of the 
sternum, that of an American species, Chordeiles popetue, is figured (Baird, Brewer, and 
Ridgway, N. Amer. Birds, ii. p. 420) with two notches, and a South-American Nightjar, 
Steatornis caripensis, forms an intermediate link between the two subfamilies, having the 
five phalanges on the outer toe and the unpectinated claw of the middle toe of the Podar- 
ginee, but nevertheless agreeing with the Caprimulginz in only having one notch on each 
side of the posterior margin of the sternum. A hasty study of both the internal and the 
external characters of the various families of birds might almost lead to the conclusion 
that every bird is related to nearly every other bird, that no characters are constant, and 
that it is impossible to determine whether any of them have any taxonomic value cr 
not, 
Ke 
