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extensive than the green ground colour and in this variety 
(Plate XLIII., fig. 14) dull white patches are often pres- 
ent. Sometimes both sexes have the green ground colour 
replaced by pale orange-brown and as this difference has 
been noticed in many fresh specimens it is not the result 
of fading. The dark coloured variety of the female here 
figured was described by Butler as a distinet species under 
the name of Charagia hectori. 
The transformations of this insect are very interesting. 
The female lays about two thousand small, round, yellow- 
ish eggs, which she seems to deposit quite indiscriminately. 
The young larvae consequently have to find their way 
along the ground to the stems of their food-plant, a large 
percentage no doubt perishing before they succeed in doing 
so, and it seems likely that the great fecundity of the 
female has arisen in order to provide against a heavy mor- 
tality, during the earliest period of the insect’s life. The 
eggs of H. virescens become black a few hours after they 
are laid, and the same peculiarity is observable in the eggs 
of many species belonging to the closely allied genus 
Porma. The foodplants of this insect are very numerous; 
the following are a few of them:—Wineberry or New Zea- 
land Currant (Aristotelia racemosa), Carpodetus serratus 
and Hoheria populnea, apparently the favourites; puriri 
(Vitex lucens); mangeao, (Litsaea calicaris); manuka 
(Leptospermum ericoides) ; kiki (Astelia Solandri) ; black 
maire (Olea Cunninghamit) ; titoki.(Alectryon excelsum) ; 
ngaio (Myoporum laetum); kamahi (Weinmannia race- 
mosa) ; beech (Nothofagus) ; Leucopogon fasciculatus, and 
Griseama lucida. In cultivated places willows, silver 
beeches, oaks and apple trees have been found pierced with 
the burrows of this insect. The larva tunnels the stems of 
these trees, feeding entirely on the wood, which it bites off 
with its strong mandibles. 
For the most part it inhabits the main stem of the 
tree, its gallery always having an outlet, which is covered 
with a curtain of silk and refuse spun exactly level with 
the surrounding bark, and very inconspicuous. These bur- 
rows usually run towards the ground, and are mostly two 
or three inches from the surface of the trunk. In some 
instances the larvae inhabit branches, in which case, if 
they are small, the tunnels are made near the centre. Later 
on in its life, but long before its transformation into the 
pupa, the caterpillar of this insect constructs a far more 
complicated burrow than the above. It consists of a spa- 
cious, irregular, but shallow cavity, just under the bark, 
having a very large opening to the air, which is entirely 
covered with a thin silken curtain, containing numerous 
fragments of wood, and closely resembling, in general 
appearance, an ordinary patch on the bark. Three large 
tunnels open into this shallow cavity: one in the centre, 
which runs into the middle of the stem, and one on each 
side, which run right and left just under the bark. These 
lateral tunnels are usually very short, but sometimes they 
extend half-way round the tree, and oceasionally even join 
one another on the opposite side. Distinct lateral burrows 
358 XVIUI—THE HEPIALIDAE. 

are, however, not found in the stems of Carpodetus seria- 
tus. The central tunnel has a slightly upward direction 
which effectually prevents it from becoming flooded in wet 
weather; in smaller trees it often reaches as far as the 
middle of the trunk, where, in the case of mature larvae, at 
appears to suddenly terminate. This, however, is not the 
ease, for, if the gallery floor be carefully examined near 
its apparent termination, a round ld will be found, com- 
pactly constructed of very hard, smooth silk, and corres- 
ponding with the surrounding portion of the tunnel so 
exactly that it almost escapes detection. When this lid is 
lifted a long, perpendicular shaft is disclosed, which runs 
down the middle of the tree to a depth of about 6 inches, 
and is about $ inch in diameter. The upper end of this 
shaft is lined with sulk, which forms a framework on which 
the lid rests when closed. The lid itself is of a larger size 
than the orifice which it covers, and is more or less adher- 
ent to the silken frame-work, which makes it very difficult, 
if not impossible, to force it open from the exterior, espe- 
cially as it always fits down very closely as long as the 
insect remains in its burrow. The object of this contriv- 
ance is, no doubt, to prevent the ingress of enemies, large 
numbers of spiders, slugs, woodlice, and various orthoptera 
being frequently found in both central and lateral tunnels, 
but they are quite unable to pass the lid. The galleries of 
individual larvae are all wonderfully alike, the only differ- 
ences observable being in the length of the perpendicular 
shaft, and in the length anid direction of the horizontal 
burrow, which is sometimes curved. These variations are 
usually caused by the presence of other tunnels in the tree, 
which the larva appears to carefully avoid; at least I have 
very seldom known an instance where a larva has allowed 
its tunnel to communicate with another one, whether in- 
habited or otherwise, and this precaution is necessary for 
the insect’s safety. It is noticeable that the individuals 
inhabiting one tree are very often of the same age. 
A specimen of this larva, attacked by the Sphaeriu 
fungus, whilst in its burrow in the tree, was once shown 
to me by the late Mr. N. J. Tone. This is the only authen- 
ticated instance of the conversion of the larva of the 
present species into a ‘‘ vegetable caterpillar ’’ although, 
prior to the discovery of its life history, the older natural- 
ists imagined that all the vegetable caterpillars found in 
New Zealand belonged to Hepalus virescens. It is now, 
of course, well known that they are referable to the sub- 
terranean larvae belonging to the closely allied genus 
Porina. 
The caterpillar, when full grown, measures from 24 to 3 
inches in length. It is tolerably uniform in thickness, and of a 
dull yellow colour. The head is large, dark brown, very irregu- 
larly striated, and covered with a few short bristles. The sec- 
ond segment is hard and shining with the back and sides ruddy- 
brown. Its spiracle, which is very large, is situated near the 
posterior margin, and a little above it there is a dull black spot, 
filling a slight concavity about the same size as the spiracle it- 
self. Each remaining segment has on its dorsal surface two 
horny plates, and two similar plates are situated on each side 
immediately below the spiracle. The body of the larva is thinly 



