THE REST HARROW (_Aplasta ononaria_).
This greyish-brown moth has two darker, sometimes reddish, cross lines on
the fore wings, and one such line on the hind wings. It is presumably only
to be regarded as an accidental visitor to England. The first record was of
a specimen captured in the Warren at Folkestone in July, 1866, and since
that year others were obtained in the same locality, but apparently not
more than about half a dozen altogether. None seems to have been recorded
for over thirty-five years. The specimen, whose portrait is shown on Plate
38, Fig. 3, was obtained from Dresden.
Abroad, the range includes Central and Southern Europe, Asia Minor, Syria,
and Armenia.
THE GRASS EMERALD (_Pseudoterpna pruinata_).
When freshly emerged from the chrysalis, the species represented by Figs. 6
to 8 on Plate 38 is of a beautiful blue-green colour, but in course of time
a greyish shade creeps over the wings. The dark cross lines vary in
intensity; in some specimens well defined and blackish, in others very
faint, and hardly discernible; occasionally, the space between the lines on
the fore wings is dark shaded; the whitish submarginal line is not always
present. This species is the _cythisaria_ of Schiffermiller, and the
_cytisaria_ of other authors.
The caterpillar (figured on Plate 41, Fig. 1, from a coloured drawing by
Mr. A. Sich) is green, with three lines along the back, the central one
dark green, the others whitish; a pinkish stripe low down along the sides,
the points on the head and the first and last rings of the body are often
pink also. It feeds on pettywhin (_Genista anglica_), also on broom
(_Cytisus scoparius_) {102} and gorse (_Ulex_); in captivity it seems to
thrive on laburnum. Most frequently obtained in the springtime after
hibernation.
The moth is to be found in June and July on moorlands and commons pretty
well throughout the British Isles, but it seems not to have been noted
north of Perthshire, in Scotland.
Odd specimens have been known to occur in late August or early September,
but this is quite exceptional.
THE LARGE EMERALD (_Geometra papilionaria_).
This charming green species (Plate 40, Figs. 1 and 4) varies in tint and in
the distinctness of the whitish wavy cross lines. In some examples, one or
other of the lines is absent, and far more rarely there is but little trace
of any of these markings. Occasionally, the discal mark is preceded by a
whitish wedge-shaped spot on the fore wings (ab. _cuneata_, Burrows).
When newly laid the eggs are whitish, but soon change to greenish yellow,
and finally to pinkish.
The caterpillar hatches in late summer, and feeds on birch, hazel, and
beech, until the leaves begin to fall in the autumn; it then constructs a
carpet of silk on a twig, and near a bud, upon which it takes up its
position for the winter. When thus seen, its reddish brown colour,
variegated more or less with green, assimilates so closely with its
surroundings that the creature is not easy to detect. In the spring, when
it awakens, the green colour increases in extent as the buds open and the
leaves unfold; when they are fully expanded, the caterpillar sits among the
foliage towards the tip of a twig, and is then almost entirely green, the
reddish brown only showing on the head, slightly on the warts, and more
distinctly on the hinder parts which are in touch with the twig. The
chrysalis, enclosed in a flimsy silken web among the dead leaves, usually
on the ground, is of a delicate green colour, dotted with buff on the back,
and shaded with buff on the wing cases. The early stages are figured on
Plate 42.
[Illustration]
2 Pl. 40.
1, 4. LARGE EMERALD.
2, 3. SMALL EMERALD.
[Illustration]
2 Pl. 41.
1. GRASS EMERALD: _caterpillar_.
2. BLOTCHED EMERALD: _caterpillar_.
3. COMMON EMERALD: _caterpillar_.
{103} The moth is out in June and July, and may occasionally be beaten out
of a hedge or bush, but is most frequently obtained late at night, when it
is active on the wing, and is attracted by a brilliant light.
The species occurs in woods, on heaths and moors, and in fens, throughout
the British Isles, except the most northern parts of Scotland and the
isles.
Abroad, the range extends to Amurland and Japan.
THE SMALL EMERALD (_Geometra vernaria_).
This species (Plate 40, Figs. 2 and 3) is smaller than the last mentioned,
the green colour is of a softer tint, and the lines crossing the wings, two
on the fore wings and one on the hind wings, are whitish, and not waved.
The caterpillar hatches from the egg in August, and after hibernation is to
be found in May and June on Traveller's Joy or Old Man's Beard (_Clematis
vitalba_). It is then green, with white dots arranged in lines along the
back and sides; the head is deep reddish brown, and this, and also the
first and last rings of the body, have raised points. Transformation to the
greenish chrysalis is effected among the leaves, drawn together with silk.
(Plate 44, Figs. 3 and 3a.)
The moth flies in the evening in July and August, and in the daytime may be
disturbed, by the application of the beating stick, from its retreats in
hedges, etc., where the food plant flourishes. Found in most of the
southern and eastern counties of England, most frequently on the chalk; its
range extends to Worcestershire. Except that it has been recorded as a
doubtful inhabitant of Ireland, the species does not appear to occur
elsewhere in the British Isles. The distribution abroad extends to
Amurland. {104}
THE BLOTCHED EMERALD (_Euchloris_ (_Comibaena_) _pustulata_).
When quite fresh, this moth (Plate 43, Fig. 1) is exceedingly pretty; the
pale blotches vary a little in size, as also do the reddish marks upon
them.
The caterpillar adorns itself with particles of its food as soon as it
leaves the egg in July; after hibernation it uses the scales or husks of
the oak buds for the same purpose. When stripped of its trappings it is
found to be reddish brown in colour, with three slightly darker lines along
the back; hooded bristles arising from raised brownish spots afford means
for the attachment of the masquerading outfit, each moiety of which is
covered with silk on one side before being placed in the required position.
When beating oaks for larvae in May and June, the contents of the umbrella
or beating tray should not be too hastily thrown away, but allowed to
remain therein for awhile, and closely watched for any movement among the
litter. The spectacle of a cluster of oak bracts suddenly becoming active
will certainly arouse curiosity, and on examination the cause of the
commotion will frequently be found to be the caterpillar of this species.
(Plate 41, Fig. 2; after Auld.)
The moth is out in June and July, and flies at dusk in and around oak
woods. In the daytime it may be jarred from its perch in oak trees, and
once I found a specimen on a fence in the Esher district. It has been known
to visit light, and examples of a September emergence have been recorded.
As a British species it only inhabits England, and it has been noted from
Staffordshire and Leicester, but seems to be rare in the midland counties
generally. It is more frequently found in the southern and eastern
counties.
Abroad, the range extends through Central Europe to Southern Sweden, S.
Russia, N. Asia Minor, and Andalusia. {105}
THE ESSEX EMERALD (_Euchloris smaragdaria_).
In some examples of this species (Plate 43, Figs. 2, 3) the green colour is
brighter than in others, and very occasionally it is tinged with bluish;
typically, there are white cross lines on the fore wings, but the inner one
is not infrequently absent, and more rarely both are missing. The white
central spot is very rarely absent, and the edges of the fore wings are
yellowish.
The caterpillar feeds on the sea wormwood (_Artemisia maritima_), and
adorns itself with fragments of its food plant in much the same manner as
that of the species last referred to. Although obtained in the autumn in
some numbers from its food plant, it seems to have been rarely met with in
the spring after hibernation. It is, therefore, advisable to collect the
caterpillars about September, and transfer them to plants of the garden
_Artemisia abrotanum_, locally known as "Southernwood," "Old man," or
"Lad's love," or, where available, wormwood (_A. absinthium_) will suit it
admirably. Upon either of these plants the larvae will hibernate, feed up
in the spring, and become full grown about May. The early stages are
figured on Plate 42, larva and pupa from photos by Mr. H. Main.
The moth is out in June and early July, but it is rarely seen in the open,
although over sixty years ago a few specimens were put up from among grass
and netted at St. Osyth; in later years an example or two have been taken
at Sheerness in Kent. Possibly, others may also have been captured in one
or other of the insect's haunts, but records are silent on the matter.
Barrett mentions a specimen emerging in September, and the Rev. C. R. N.
Burrows notes that part of a brood of caterpillars reared from eggs, and
fed on _A. absinthium_, attained the moth state during the autumn. So far
as concerns {106} the British Isles it seems to be almost exclusively an
inhabitant of the salterns, or sea marshes of Essex.
Abroad, the species occurs inland, and is not confined to the coast; its
range extends eastwards to Siberia and Amurland.
THE SMALL GRASS EMERALD (_Nemoria viridata_).
This species, represented on Plate 43, Figs. 5 and 6, is readily
distinguished by its small size and the well-defined white cross line on
each wing. In most examples there is a more or less distinct whitish inner
line on the fore wings. Ab. _mathewi_, Bankes, has all the wings dusted
with orange scales, more especially on the outer marginal areas. A few
examples of this form were reared in 1905, with a number of normal
specimens, from eggs laid by a female captured in South Devonshire.
The caterpillar (figured from a skin on Plate 44, Fig. 1) is green,
roughened with whitish points; a dusky line along the middle of the back,
marked on the front and end rings, also between the rings, with purplish
red. Head, and first ring of the body, notched, the points reddish; last
ring of the body pointed. When at rest on a twig it assumes a rigid
posture, and the legs are tightly drawn together. It feeds on heather,
sallow, and birch, but the general experience appears to be that in
captivity it thrives best on a diet of hawthorn, and is especially partial
to the young shoots. It may be obtained in July and August, and the moth
comes out in the following May or June. In 1905, Mr. A. J. Scollick reared
some caterpillars from eggs laid June 2nd, and hatched June 16th; all duly
pupated, and a moth came up on December 20th of that year. Four others
appeared in January and February, 1906.
[Illustration]
2 Pl. 42.
1, 1a, 1b, 1c. LARGE EMERALD: _egg, caterpillars and chrysalis_.
2, 2a. ESSEX EMERALD: _eggs, caterpillar and chrysalis_.
[Illustration]
2 Pl. 43.
1. BLOTCHED EMERALD.
2, 3. ESSEX EMERALD.
4, 7. LITTLE EMERALD.
5, 6. SMALL GRASS EMERALD.
8, 9. COMMON EMERALD.
{107} The Rev. F. E. Lowe states that in Guernsey the species occurs
exclusively among furze on cliffs by the sea, and chiefly where the plant
is cut down from time to time. In Britain it inhabits heaths and mosses,
but is very local. It is found in the English counties of Hants (New
Forest, etc.), Dorset (Poole Heath, etc.), Devon (Woodbury, Exeter
district, etc.), Norfolk (Horning), Worcester (Malvern district, rare);
also at Methop, Witherslack, and other localities in Westmoreland and
Cumberland. Only doubtfully recorded from Scotland and Ireland.
Abroad, the range extends to Amurland, Corea, and China.
THE LITTLE EMERALD (_Iodis lactearia_).
The green tint in this species (Plate 43, Figs. 4 and 7) is even more
unstable than in others of the group. When quite fresh the wings can often
only be described as whitish with a delicate green tinge, but even when the
greatest care is taken to preserve it, the colour is apt to fade.
The caterpillar (Plate 44, Fig. 2, from a coloured drawing by Mr. A. Sich)
is long and thin, with two points on the edge of the first ring, and one on
the last ring, of a bright green colour, paler between the rings; the spots
along the back are reddish, as also is the whitish-fronted deeply notched
head. It feeds on the leaves of various trees and bushes, such as birch,
oak, hawthorn, sallow, etc. It may be obtained by beating or searching from
August to September.
The moth is out in May and June, in some seasons later, and may be beaten
out of hedges, as well as from trees in woods. Generally distributed, and
often common, throughout England, Wales, and Ireland. In Scotland it is
locally common in Clydesdale, and occurs in other southern parts of that
country.
Abroad, the range extends to Amurland, Corea, China, and Japan.
THE COMMON EMERALD (_Hemithea strigata_).
When freshly emerged from the chrysalis, this species (Plate 43, Figs. 8
and 9) is darkish green, but it soon fades to a greyish {108} tint. Easily
distinguished by its shape, and by the chequered fringes. It is the
_aestivaria_ of Hubner, and _thymiaria_ of Guenee. The long, thin, green
caterpillar is ornamented with reddish brown, the V-shaped marks on rings 5
to 8 are sometimes whitish; head, deeply notched, brown; the first ring of
the body is also notched. It hatches from the egg in August, when it is
said to feed on mugwort (_Artemisia vulgaris_), and other low plants; after
hibernation it feeds on the foliage of oak, birch, hawthorn, rose, etc.,
and attains full growth in May or June. In late June and in July the moth
may be put up from the undergrowth in woods, or from bushes in
well-timbered hedgerows bordering lanes and fields. Specimens so obtained
are poor in colour as a rule, and it is well, therefore, to rear the
species from the caterpillar. (Plate 41, Fig. 3; after Hofmann.) This
remark applies to all "Emeralds."
The species is often common in the south and east of England, and along the
western side, including Wales, up to Cheshire and Lancashire, but it
becomes local in Worcestershire and northwards. There are few records of it
from Yorkshire, and its occurrence in Durham, Northumberland, and Scotland
is doubtful. In Ireland it appears to be widely distributed, but scarce.
The range abroad extends to Amurland, Corea, and Japan.
[_Thalera fimbrialis_. A specimen of this Central European species
(identified by the late Mr. C. G. Barrett) was taken on August 7, 1902, by
Mr. C. Capper, from a blade of grass growing on a slope under Beachy Head,
Sussex. The species is somewhat similar in appearance to _H. strigata_, but
is larger; the hind wings are notched above the angle on the outer margin;
the fringes of all the wings are chequered with red, and the antennae of
the male are bipectinated.] {109}