cue 
•dually advanced from a very diminutive fize to the 
_greated the yolk acquires before it is received into the 
oviduft. The appearance of one, killed on the 3d of 
July, was very different: in this I could didinctly trace 
a great number of the membranes, which had difeharged 
oiks into the ovidudt, and one of them appeared as if it 
ad parted with a yolk the preceding day. The ovarium 
flill exhibited a cinder of enlarged eggs, but the moft 
forward of them was fcarcely larger than a muftard-feed. 
“ I would not be underftood to advance, that every 
egg, which fwells in the ovarium at the approach or 
commencement of the propagating fcafon, is brought to 
perfection; but it appears clearly, that a bird, in obedi¬ 
ence to the dictates of her own will, or to fome hidden 
caufe in the animal economy, can either retard or bring 
forward her eggs. Betides the example of the common 
fowl, above alluded to, many others occur. If we de- 
llroy the nelt of a blackbird, a robin, or alrnoft any fmall 
bird, in the fpring, when Ihe has laid her ufual number of 
eggs, it is well-known to every one, who has paid any at¬ 
tention to inquiries of this kind, in how Ihort a fpace of 
time the will produce a frelh fet. Now, had the bird 
been fuffered to have proceeded without interruption in 
her natural courfe, the eggs would have been hatched, 
and the young ones brought to a-date capable of provid¬ 
ing for themfelves, before (lie would have been induced 
to make another ned, and excited to produce another fet 
of eggs from the ovarium. If the bird had been deftroy- 
ed at the time Ihe was fitting on her fird laying of eggs, 
diffection would have (hewn the ovarium containing a 
great number in an enlarged date, and advancing in the 
ufual progreffive order. Hence it plainly appears, that 
birds can keep back, or bring forward, (under certain 
limitations,) their eggs at any time during the feafon ap¬ 
pointed for them to lay ; but the cuckoo, not being fub- 
jeCt to the common interruptions, goes on laying from 
the time flie begins till the eve of her departure from 
this country ; for, although old cuckoos in general take 
their leave the firft week in July (and I never could fee 
one after the fifth of that month, though I conceive it 
poffible that here and there a draggling cuckoo may be 
feen after this time) ; yet I have known an indance of 
an egg’s being hatched in the ned of an hedge-fparrow fo 
late as the 15th. And a farther proof of their continu¬ 
ing to lay till the time of their leaving 11s may, I think, 
be fairly deduced from the appearances on dilfedtion of 
the female cuckoo, above-mentioned, killed on the 3d 
of July.” 
The growth of the young cuckoo is uncommonly 
rapid. Its chirp is plaintive, like that of the hedge- 
fparrow ; but the found is not acquired from the foder- 
parent, as it is the fame whether it be reared by the 
hedge-fparrow or any other bird. It never acquires the 
adult note during its day in this country. The domachs 
of young cuckoos contain a great variety of food. On 
diffeCting one that was brought up by wagtails, and fed 
by them at the time it was fhot (though it was nearly of 
the fize and fulnefsof plumage of the parent bird), Mr. 
Jenner found in its domach the following fubdances: 
Hies and beetles of various kinds; fmall fnails with 
their fhells unbroken; grafhoppers; caterpillars; part 
of a horfe-bean ; a vegetable fubdance, refembling bits 
of tough grafs, rolled into a ball; and the feeds of a 
vegetable that refembled thofe of the goofe-grafs. In. 
the domach of one fed by hedge-fparrows, the contents 
were almod entirely vegetable; fuch as wheat, fmall 
vetches, &c. “ But this (fays our author) was the only 
indance of the kind I had ever feen, as thefe birds in 
general feed the young cuckoo with fcarcely any thing 
but animal food. However, it ferved to clear up a 
point, which before had fomewhat puzzled me; for, 
having found the cuckoo’s egg in the ned of a green 
linnet, which begins very early to feed its yotfng with 
vegetable food, I was apprehenfive, till I faw this fa£t, 
that this bird would have been an unfit foder-parent for 
Vol. V, No. 285. 
ULUS, 4.J7 
the young cuckoo. The titlark, I obferve, feeds it 
principally with gradioppers. But the mod lingular 
fubdance, fo often met with in the domachs of young 
cuckoos, is a ball of hair,' curioufly wound up. I have 
found it of various fizes, from that of a pea to that of a 
fmall nutmeg. It feems to be compofed chiefly of 
horfe-hairs ; and from the refemblance it bears to the 
infide covering of the ned, I conceive the bird fwallows 
it while a nedling. In the domachs of old cuckoos are 
often feen maffes of hair ; but thefe had evidently once 
formed a part of the hairy caterpillar, which the cuckoo 
often takes for its food.” 
There feems to be no precife time fixed for the depar¬ 
ture of young cuckoos. Mr. Jenner believes they go 
off in fuccedion, probably as loon as they are capable 
of taking care of themfelves; for, although they flay 
here till they become nearly equal in fize and growth of 
plumage to the old cuckoo, yet in this very date the 
iodering care of the hedge-fparrow is not withdrawn 
from them. “I have frequently (fays he) feen the 
young cuckoo of fuch a fize, that the hedge-fparrow has 
perched on its back, or half expanded wing, in order to 
gain fufficient elevation to put the food into its mouth. 
At this advanced dage, I believe that young cuckoos 
procure fome food for themfelves ; like the young rook, 
for indance, which in part feeds itfelf, and is partly fed 
by the old ones, till the approach of the pairing feafon. 
It they did not go oft’ in fuccedion, it is probable we 
fliould fee them in large numbers by the middle of Au- 
gud ; for, as they are to be found in gl'eat plenty wheat 
in a nedling date, they mud now appear very numerous, 
fince all of them mud have quitted the ned before this 
time. But this is not the cafe ; for they are not more 
numerous at any feafon than the parent-birds are in the 
months of May and June. 
From what has been faid, it becomes evident, that 
the fame indinftive impulfe, which direfls the cuckoo 
to depofit her eggs in the neds of other birds, directs 
her young one to throw out the eggs and young of the 
owner of the ned. The fcheme of nature would be in¬ 
complete without it; for it would be extremely difficult, 
if not impoflible, for the little birds dedined to find fuc- 
cour for the cuckoo, to find it alfo for their own young 
ones after a certain period; nor would there be room 
for them to inhabit the ned. It is fuppofed, that there 
are more male cuckoos than females; fince two are 
often feen in difpute where a third has been in light; 
which, no doubt, was of the oppofite fex. Mr. Pen¬ 
nant obferved, that five male birds were caught in a 
trap in one feafon ; and Dr. Latham fays, that, “out of 
at lead half a dozen that I have attended to, my chance 
has never directed me to a female ; and it is to be wiflied, 
that future obfervers may determine whether our obfer- 
vations have rife only in chance, or are founded on the 
general circumdance.” He believes that the male birds 
are more liable to be fliot, their note directing the gun¬ 
ner where to take aim, while the female is fecured by her 
filence. 
Cuckoos may be, and often are, brought up tame, fo 
as to become familiar. They will eat in this date bread 
and milk, fruits, infedfs, eggs, and flefli either cooked or 
raw ; but, in a date of nature, they chiefly live on cater¬ 
pillars. When fat, they are faid to be as good eating as 
a land-rail. The French and (Italians eat them to this 
day. The ancient Romans admired them greatly as 
food : Pliny fays there is no bird which can be compared 
to them for delicacy. 
The young cuckoos never fing during their fird year, 
and the old ones ceafe towards the end of June, at lead 
their fong is then unfrequent. But this filence does not 
announce their departure. It is the fcarcity of infedls, 
no doubt, which determines them to retire to warmer 
climates: they migrate for the mod part into Africa, 
fince they are feen twdee a-year pafling and repading the 
ifland of Malta; its real retreat, however, is ablolutely 
5 T unknown. 
