


14 III—HABITS AND DISTRIBUTION OF N.Z. LEPIDOPTERA. 
Of the great family of night flying moths generally 
known to entomologists as the Noctuidae (Plates VI.—X.), 
over one hundred species are found in New Zealand but, 
with the exception of the Melanchrid group, most of these 
are scattered stragglers, which appear to be the result of 
accidental wind-borne immigration over a wide expanse of 
sea. Practically all the New Zealand species are night 
fliers, although a stray specimen may sometimes be observed 
flying in hot sunshine, but this is usually the result of some 
untimely disturbance. Most of the Noctwidae are dull 
coloured, their general wing pattern assimilating with the 
varied hues of dead leaves, and as they are most abundant 
during the autumn, the value of this form of protective 
colouring is obvious. 
The family Geometridae (Plates XI.—XVIII.) com- 
prises the most beautiful, varied, and extensive assemblage 
of the larger moths in New Zealand. These insects are 
more in evidence than the sombre Noctuidae, and many 
species fly very readily in the day time, whilst some only 
do so when disturbed. The remarkable long-bodied moths 
belonging to the genus Tatosoma frequent forests, and are 
usually found resting on tree trunks by day or flying over 
blossoms in the evening. The charming little Hlvia 
glaucata when resting folds its wings so as to resemble the 
uneven surface of a lichen. The very beautiful and exten- 
sive genus Chloroclystis contains species which frequent 
both forests and open country, and from their extreme 
variability, both in the larva and final conditions, present 
unusual difficulties to the student. Most of the species rest 
by day, with outspread wings, on tree trunks or rock sur- 
faces, their protective pattern being often extremely com- 
plex. All the species are very much on the alert, and fly 
with considerable rapidity when in any way disturbed. In 
Eucymatoge both pairs of wings are very delicately 
striped so as to resemble bark, the insects always resting 
with them outspread. Hydriomena has the hind-wings 
without definite markings. The species fly freely in the 
day-time when disturbed, but not otherwise. They rest 
with the hind-wings almost entirely covered with the fore- 
wings, the whole insect then approximating to the shape of 
a triangle. Their larve feed amongst dead leaves and low 
plants, during the winter, and hence are very seldom ob- 
served. The larve of the allied genus Asaphodes have 
similar habits. The odd little Paradetis porphyrias in- 
habits ferny glens in beech forests and flies by day with a 
mazy flight close to the ground. The large genus 
Xanthorhoe, more extensively represented in New Zealand 
than elsewhere, comprises a number of highly ornamental 
insects, many of which are widely distributed throughout 
the country. None are regular day-fliers, but all imme- 
diately take wing on the slightest disturbance. The genus 
Notoreas and its allies Lythria and Dasyuris are nearly 
all gaily coloured insects, and fly very rapidly in the hot 
sunshine. Most of the species frequent high mountainous 
regions, many are very local, and from their striking ap- 
pearance are much prized by collectors. The pretty little 
Leptomeris rubraria swarms over dried-up pastures, in Feb- 
ruary and March, and is also an abundant species in Aus- 
tralia. The dark-coloured little species belonging to the 
genus Dichromodes frequent rock surfaces, exposed to hot 
sunshine, and fly immediately on the approach of an in- 
truder. The genus Selidosema comprises a large number 
of interesting species, chiefly frequenting forest districts. 
They rest quietly on tree-trunks or palings during the day- 
time and, unless disturbed, seldom take wing until the dusk 
of evening. The genus Azelina and its allies Gargaphia 
and Sestra include another assemblage of forest-dwelling 
insects. Their larve feed on ferns, and the perfect insects 
are extremely variable. The closest allies to these genera 
are found in South America. The species included in the 
genus Declana have very stout bodies and, in superficial 
appearance, somewhat suggest some of the European species 
of Notodontidae. Their flight is strictly nocturnal, but 
they may be found resting on tree-trunks or palings 
during the day-time. Declana glacialis differs however 
very strikingly from its congeners. It frequents mountains 
in the South Island at elevations of from 3,000 to 4,000 
feet and flies with a rushing headlong flight, in sunshine, 
especially towards sunset. 
In the great family Pyralidae (Plates XIX.—XXII. 
and XXIV.), most of the species readily take wing by day. 
The genus Crambus, which includes the well-known grass 
moths, comprises no less than forty-five endemic New Zea- 
land species, whilst there are no indigenous species in 
Australia, and the remarkable significance of this fact will 
be referred to later on. Many of the Crambi may be 
ranked amongst the most abundant of our insects. They 
often rise in swarms as we walk amongst the tussocks, where 
the greater number of the species are found. C. flexuosellus 
and C. ramosellus abound on the edges of forests, whilst the 
very large and handsome C. crenaeus, C. diplorrhous, C. 
isochytus and allied forms are rarely found, except on high 
grass-covered mountains about 4,000 feet above sea level. 
These large Crambi are, however, very uncertain in their 
appearance. They will, at times, be extremely abundant, 
whilst on another visit to the same mountain, at the same 
season, not one will be found. The brilliant little 
C. heliotes flies rapidly over damp mossy places, in hot sun- 
shine, but is very loeal. Most of the other species do not 
usually fly freely unless disturbed. On the tops of high 
mountains, and in certain other special localities, Crambus 
is replaced by the interesting and closely allied genus 
Orocrambus. The species included in Orocrambus are all 
day fliers, and very darkly coloured, enabling them to ab- 
sorb heat rapidly, and thus take advantage of the 
fitful periods of hot sunshine characteristic of alpine 
climates. The genus Scoparia (of which there are one 
hundred and four known species in New Zealand, against a 
total of only twelve species in Britain) is found in every 
part of the country but, as with most genera, is most ex- 
tensively represented in the South Island. A few of the 
dark-coloured mountain species fly by day, but the majority - 
