and the captured insect immediately finds itself overwhelmed
with the viscid saliva secreted by the faucial glands.
That the bristles along each side of the upper mandible
assist this bird while feeding on the wing, by increasing the
means of capture by the mouth, there can be little doubt—
though it is to be remarked that one section of the Family,
containing among others the American Night-Hawks {Chordedilei),
is not so provided; but the use of the serrated claw
on each middle toe is not so obvious; and zoologists have
delighted in exercising their ingenuity to explain the function
of this organ, which, equally with the maxillary bristles,
is not possessed by all the Caprimulgidce, while it is found
also in several other groups of birds by no means related to
them; Gilbert White thought he had distinctly seen the
Goatsucker “ put out its short leg whilst on the wing, and,
by a bend of the head, deliver somewhat into its mouth.”
Hence he not unnaturally inferred that the use of the serrated
claw was to aid in the capture of prey. Atkinson also
quotes (Comp. Orn. p. 108) the opinion of a correspondent
to the same effect, but the very weak grasping-power of the
bird’s foot forbids our accepting this explanation. Other
uses have been assigned to this organ, namely to comb out
the rictal bristles—which seems inadmissible, since many
genera of the Family want them though possessing the serrated
claw—or to clear the mouth from the sharp hooks on
the legs of insects—as suggested by Mr. Hayward (Mag.
N. H. iii. p. 449) and others, while some have supposed it
is supplied as a means of getting rid of parasites—a process
which Wilson says he actually saw in the case of a captured
bird of an allied American species, Gaprimulgus carolinensis*.
Mr. Sterland believes (B. Sherw. p. 174) that this feature
is correlated with the bird’s practice of sitting, as before
stated, lengthways on a branch—the serrated edge of the
claws being “ placed in exactly the best position for preventing
the foot from slipping sideways ”—an inconvenience
The observation is doubtless true so far as it goes, but too much, importance
must not be attached thereto. Birds generally use their claws for this purpose,
and birds in captivity especially do so if denied the means of dusting themselves.
which is further guarded against by the lateral position of
the hind-toes—and remarks in corroboration of this theory
that some exotic Nightjars, of the genera Podargus and
JEgotheles especially, which have the middle claw smooth
and the hind-toe directed backwards, perch across the branch
on which they sit. Amid all these suppositions it seems
best to confess that the true function of the organ has yet to
be determined, the last being perhaps the most plausible,
though not applying to all birds similarly furnished.
The Nightjar makes no nest whatever, but lays its two*
eggs on the ground, sometimes choosing the bare soil, but
nearly as often placing them on lichen or moss of short
growth. After incubation has made some progress, a slight
hollow, caused no doubt by the weight of the sitting bird
(light though it be) is perceptible; but there is no sign of
any depression being formed intentionally, nor is any shelter
sought. Yet markless as the spot may be, it is often used
year after year by the mother, the eggs being laid within a
few inches of where their predecessors of the summer before
had been deposited. So far as is actually known, only one
brood, accidents excepted, is produced in the season, but
since eggs may be found from the end of May to the end of
July—or even in August (Journ. f. Orn. 1860, p. 472)—a
second seems to be occasionally possible. They are generally
laid about the beginning of June, and are of elongated
form, having both ends nearly equal, white, sometimes
tinged with cream - colour, blotched, mottled, clouded or
veined, in wonderful variety, with brownish-black, lighter
brown or lilac-grey of different shades,! and measure from
1’34 to 1*08 by from *89 to ‘78 in. The young when hatched
are covered with down, and, though remaining for some days
in their birth-place, can, it would seem, at an early age dis-
* Mr. P. Bartlett records (Zool. p. 445) the finding of two young birds and
one egg in a “ nest” ; but there is nothing to shew that all were the offspring of
one mother.
f No reasonable person can doubt the protective nature of the colouring of
these eggs, exposed as they are to innumerable dangers. Some species of Nightjars
are said to remove their eggs in their mouth if they have been found and
handled. The Editor cannot find proof that our own bird takes this precaution.
VOL. II. 3 D