Iora zeylonica (Gm.) _et_ I. typhia (_Linn.), Jerd. B. Ind._
ii, pp. 101, 103.
Aegithine tiphia (_Linn.), Hume, Rough Draft N. & E._ nos. 467, 468.
I have already on several occasions (see especially 'Stray Feathers,'
1877, vol. v, p. 428) recorded my inability to distinguish as
distinct species _Ae. tiphia_ and _Ae. zeylonica_. I am quite open to
conviction; but believing them, so far as my present investigations
go, to be inseparable, I propose to treat them as a single species in
the present notice.
The Common Iora (the genus, though possibly nearly allied, is too
distinct from _Chloropsis_ to allow me to adopt, as Jerdon does, one
common trivial name for both) breeds in different localities from May
to September. I have taken nests and eggs of typical examples of both
supposed species, and have had them sent me with the parent birds by
many correspondents; and though both vary a good deal, I am convinced
that all the variations which occur in the nests and eggs of one
race occur also in those of the other. If one gets only two or three
clutches of the eggs of each, great differences, naturally attributed
to difference of species (see Captain Cock's remarks, _infrà_), may
be detected; but I have seen more than fifty, and, so far as I am
concerned, I have no hesitation in asserting that, as in the case of
the birds so in that of their nests and eggs, no constant differences
can be detected if only sufficiently large series are compared.
The birds build usually on the upper surface of a horizontal bough, at
a height of from 10 to 25 feet from the ground. Sometimes, when the
bough is more or less slanting, the nest assumes somewhat more of a
pocket-shape. Occasionally it is built between three or four slender
twigs, forming an upright fork; but this is quite exceptional.
As a rule nests of the Iora very closely resemble those of
_Leucocerca_, so much so that when I sent a beautiful photograph of a
nest, which I had myself watched building, of the latter species to
Mr. Blyth, he unhesitatingly pronounced it to be a nest of the former.
There is, however, a certain amount of difference; the Iora's nests
are looser and somewhat less compact and firm. My experience does not
confirm Mr. Brooks's remarks (_vide infrà_) that they are usually
shallower; on the contrary all those now before me are, as indeed all
the many I can remember to have seen were, deep, thin-walled cups,
which had been placed on more or less horizontal branches, not
uncommonly where some upright-growing twig afforded the nest
additional security. The egg-cavity averages about 2 inches in
diameter, and varies from an inch to 1¼ inch in depth; the walls,
composed of vegetable fibres, and varying in different specimens
from only one eighth to three eighths of an inch in thickness, are
everywhere thickly coated externally with cobwebs, by which also the
nest is firmly attached to the branch on which it is seated, as well
as, where such adjoin the nest, to any little twig springing from that
branch. Interiorly they are more or less neatly lined with very fine
grass-stems. The bottom of the nest in its thinnest part is rarely
above one eighth of an inch in thickness, but running, as it so often
does, down the curving sides of the branch, it becomes a good deal
thicker, and where placed on a small branch, say not exceeding an
inch in diameter, the lateral portions of the bottom of the nest are
sometimes more than half an inch in thickness.
One nest which I obtained recently in the Botanical Gardens at
Calcutta was built in an upright fork of four slender twigs; and in
this case the bottom of the nest was obtusely conical, and at its
deepest point may have been nearly an inch in depth. I have never seen
a similar nest.
The eggs are normally three in number, but I have at times found only
two, and these more or less incubated.
Mr. Brooks, writing of a nest he took in the Mirzapoor District,
says:--"Did you ever get particulars of the nest of _Iora zeylonica_
on the forked branch of a mango-tree 12 or 14 feet from the
ground? Nest composed of the same materials as that of _Leucocerca
albifrontata_, but not quite so neat and much more shallow; eggs
salmon-coloured and spotted with pale reddish brown, intermixed with a
few larger dashes of purple-grey. The bird lays in July; three eggs.
This is the only nest I have not taken since I came to India the
second time."
From Raipoor, Mr. F.R. Blewitt remarks:--"The Iora breeds from July to
September, and certainly _not_, as Dr. Jerdon supposes, twice a year.
Both birds assist in the building of the nests, and there evidently
appears to be no choice of any particular kind of tree on which to
build. I have found them indiscriminately on the mango, mowah, neem,
and other trees. The nest is invariably made either just above or
between the fork of two outshooting slender horizontal branches. It
is very neatly made, deeply cup-shaped, of grass and fibres, with
spider's web on the exterior. The maximum number of eggs is three;
they are of a pale whitish colour, marked generally, chiefly at the
broad end, with brownish spots. The brown spots vary in size on
different eggs. I secured the first eggs on the 12th July, and the
last on the 2nd September. A pair of birds were on this last date just
completing their nest, which unfortunately was destroyed by the heavy
rains."
Captain Cock says:--"_Iora tiphia_ is tolerably common at Seetapoor
(Oudh), and I have several times taken their nests and eggs. I may
here mention that I have taken eggs of _Iora zeylonica_ at Etawah, and
that knowing the birds well, I can say that it is quite a distinct
bird; although in the marking of its eggs there is a slight
resemblance, yet the nests of the two species are quite different. On
the 13th May I observed a nest of _I. tiphia_ on a young mango-tree,
at the edge of a croquet-ground in our garden. I shot both male and
female and took the eggs; the nest was placed on the upperside of a
sloping bough, was covered outside with cobweb, and lined with thin
dry grass. It contained two fresh eggs of a delicate pink colour, with
broad irregularly-shaped dashes of light brown down the sides of the
shell, not tending to coalesce in any way at either apex. Another pair
also built their nest on the edge of the same ground in another tree;
but unfortunately in a weak moment I pointed out the nest to a lady
friend, and as thereafter no one ever played croquet on the ground
without staring at the nest, the birds got disgusted and soon deserted
it."
To this I need merely add that _of course_ typical _Ae. tiphia_
and typical _Ae. zeylonica_ are very distinct, but that as every
intermediate form occurs, they are not, according to my views of what
constitutes a species, entitled to specific separation, and that as
regards nest and eggs, according to my experience, every variety in
the one is to be found in the other.
Dr. Jerdon, speaking of Southern India, remarks:--"I have seen the
nest and eggs on several occasions. The nest is deep, cup-shaped, very
neatly made with grass, various fibres, hairs, and spiders' webs; and
the eggs, two or three in number, are reddish white, with numerous
darker red spots, chiefly at the thicker end. It breeds in the south
of India in August and September; perhaps, however, twice a year."
Writing from South Wynaad, Mr. J. Darling (Junior) says:--"I found the
nest, which with the eggs and both parents I have now sent you, in the
Teriat Hills on the 24th May, at an elevation of about 2300 feet. It
was placed on, and near the extremity of, a bough, at a height of
about 10 feet from the ground. It is round, about 2 inches in height
and the same in diameter, and the cavity was about an inch or a trifle
more in depth. It is built of grass and reed-bamboo-fibres, and is
coated with spider's web. It only contained two eggs."
Both parents (sexes ascertained by dissection) are in the typical
_tiphia_ plumage, without one particle of black on either head, nape,
or back.
Mr. Davidson writes:--"In the Satara and Sholapur districts the cock
puts on his summer plumage in May and the whole back of head, neck,
and back (not rump) is glossy and black.
"This bird lays from the end of June to beginning of August. It is
very shy when building and is easily caused to forsake its nest; if a
single egg is taken from the nest it does not forsake it, however, but
lays on (three instances this year)."
Mr. W.E. Brooks has favoured me with the following very interesting
note on the habits of this Iora:--
"Ioras are very numerous and have such a variety of notes that I
thought at first there were several sorts; but as far as I can see
there is but one species. Iora spreads its tail in a wonderful manner,
and comes spinning round and round towards the ground looking more
like a round ball than a bird. All the time it descends it utters a
strange note, something like that of a frog or cricket, a protracted
sibilant sound. This bird is close to _Liothrix_ and _Stachyrhis_,
although it belongs to the plains."
Colonel Butler writes:--"A nest on the 17th August, 1880, on the
outside branch of a silk-cotton tree in Belgaum about 12 feet from the
ground, containing three fresh eggs.
"I found many other nests building all through the hot weather and
rains; but in every single instance except the present one they were
deserted before they were completed."
Major Bingham writes from Tenasserim:--"This species is common
throughout the country. As a rule its nest is well hid, but one I
saw in the compound of a house in Maulmain was placed in the exposed
leafless fork of a tree, not above six feet from the ground. It
contained no eggs when I examined it, and was deserted a day or two
after. This was in the beginning of May."
Mr. Oates remarks on the breeding of this bird in Pegu:--"Nests are
found chiefly in June and July, but the birds probably lay also in
May."
In shape the eggs are moderately broad ovals, slightly pointed towards
one end. They vary, however, a good deal, some being much more
elongated than others. They are almost entirely devoid of gloss. The
ground-colour is generally greyish white, but some have creamy and
some a salmon tinge; typically they have numerous long streaky pale
brown or reddish-brown blotches, chiefly confined to the large end,
where they often seem to spring from an irregular imperfect zone of
the same colour. The colour of the blotches varies a good deal. In
some it is a pale greyish or purplish brown; in others decidedly
reddish, or even well-marked and somewhat yellowish brown. Some pale,
purplish streaks and clouds generally underlie the brown blotches
where they are thickest, and there form a kind of nimbus. In some eggs
the markings are confined to a narrow imperfect zone of pale purplish
specks or very tiny blotches round the large end, and some of the eggs
remind one of those of _Leucocerca albifrontata_. The peculiar streaky
longitudinal character of the markings, almost wholly confined to the
large end, best distinguishes the eggs of the Ioras from those of any
other Indian bird with which they are likely to be confounded.
In length they vary from 0·63 to 0·76, and in breadth from 0·51 to
0·57: but the average of forty-seven eggs measured is 0·69, nearly, by
a trifle more than 0·54.