


100 
The pupa is enclosed in a thin cocoon, constructed 
of silk and refuse, situated on the surface of the ground. 
The perfect insect appears from September till April, 
and frequents scrubby forest, It is generally found rest- 
ing on moss-covered tree-trunks, where its green and brown 
colouring is highly protective. 
HYDRIOMENA CALLICHLORA. 
(Cidaria callichlora, Butl., Cist. Ent. ii., 509; Meyr., Trans. N.Z. 
Inst., xvi., 76; Hydriomena praerupta, Philp., ib., 1., 125.) 
(Plate XII., fig. 47 9; 48 @ Mountain form;, Plate XLVIII., 
fig. 19, variety; Plate II., fig. 3 larva.) 
This very beautiful insect has occurred at Waimarino 
and Wellington in the North Island, and at Christchurch, 
Otira, Dunedin and Invereargill in the South Island. 
The expansion of the wings is about 1 inch. The fore-wings 
are bright green with numerous blackish or dark brown wavy 
transverse lines; these form a distinct basal patch and a wide, 
strongly indented, median band which contains a black discal 
dot; there are several brownish or blackish patches on the 
terminal area traversed by a fine wavy green subterminal line; 
the veins are sharply dotted in black. The hind-wings are very 
pale greyish-white with several very faint wavy transverse lines. 
All the wings are margined with a series of black crescentic 
markings and the cilia are greyish-green. 
This species varies slightly in the intensity of the 
median band and other markings. These are, however, 
much more distinct than in H. similata and the absence of 
any reddish-brown colouring on the hind-wings is also a 
good character. The green colouring of H. callichlora is 
always much brighter than in H. similata. 
A variety of this species, sometimes found in moun- 
tainous regions, having a paler apical patch, slightly more 
dentate subterminal line and stronger projection on the 
posterior margin of the median band, has been described 
by Mr. Philpott under the name of Hydriomena praerupta. 
(Plate XII., fig. 48.) Another very remarkable variety, 
in Mr. Clarke’s collection, is figured on Plate XLVIIL., 
noo? 
The very handsome larva, which feeds on Coprosma 
rotundifolia, during the summer months, is about 1 inch in 
length, moderately slender, slightly flattened and of almost 
uniform thickness; very bright green much paler on the 
ventral surface; there is a conspicuous crimson lateral line 
sometimes edged with white and the prolegs are also 
erimson; the segmental divisions are marked in yellow, 
and there are a few isolated black bristles. Younger larvae 
have the ground colour dull greyish-green, whitish under- 
neath, and the crimson stripe is much fainter than in the 
full-grown larva. 
The pupa is enclosed in a fragile cocoon composed of 
several leaves joined together with silk and usually situated 
on the surface of the ground. 
The perfect insect appears from November till March. 
It is very local frequenting restricted areas, usually on 

*Sub-species harmonica, Clarke, Trans, N.Z. Inst., lvi., 417, 

X—THE GEOMETRIDAE. 
wind swept scrubby hill tops, where its foodplant is often 
abundant. It rests on mossy tree-trunks with the fore- 
wings folded back and the end of the abdomen curled 
upwards; this, together with the thoracic crests, greatly 
increases the insect’s resemblance to a patch of moss. 
Although larvae of all ages are to be found feeding during 
the summer, it appears probable that the species spends 
the winter either as a full-grown hybernating larva, or as 
a pupa. 
HYDRIOMENA ARIDA. 
(Melanthia arida, Butl., Cist. Ent. ii., 509; Cidaria 
Meyr., Trans. N.Z. Inst., xvi., 76. 
ib., xvii., 64.) 
chaotica, 
Cidaria arida, Meyr., 
(Plate XII., figs. 33, 34, varieties.) 
This very dark-looking species has occurred in the 
South Island at Picton, Nelson, Akaroa, Mount Hutt, 
Arthur’s Pass, Otira, Dunedin, Lake Wakatipu and Inver- 
eargill. It also occurs on Stewart Island. 
The expansion of the wings is 14 inches. The fore-wings 
are dark blackish-grey; there are two small cream-coloured 
patches on the costa at 4 and % continued across the wing as two 
curved series of small cream-coloured spots; there is a sub- 
terminal series of whitish dots. In most specimens there is a 
very broad paler brown median band with a rounded projection 
below the middle almost touching the termen; this band is 
traversed by numerous fine wavy dark brown transverse lines 
and contains a conspicuous discal dot. The hind-wings are very 
pale brownish-grey or creamy-grey; all the cilia are nearly 
black. 
This species is at once recognisable by the very dark 
colouring of the fore-wings and very broad, usually paler, 
median band. 
The perfect insect appears from December till Feb- 
ruary, and is found in forests, between 1,500 and 3,000 
feet above the sea-level, but is not a common species. 
HYDRIOMENA HEMIZONA. 
(Hydriomena hemizona, Meyr., Trans. Ent. Soc. Lond. 1897, 385.) 
(Plate XII., fig. 35 45°36 9°) 
This rather obscure-looking species has occurred at 
Waimarino, Mount Egmont, Mount Holdsworth and Cape 
Terawhiti in the North Island, and at Mount Arthur, 
Otira, Waitati, the Routeburn Valley, Lake Wakatipu, 
Longwood Range, and the Hunter Mountains in the South 
Island. 
The expansion of the wings is about 1} inches. All the 
wings are very glossy with slight bronzy reflections; the fore- 
wings are bronzy-brown with numerous wavy blackish trans- 
verse lines sometimes forming a fairly distinct median band 
which, however, is more often merged with: the basal patch; 
the outer edge of the median band has a large rounded projection 
and is often edged with white near the costa, it is rarely 
followed by an obscure reddish-brown wavy streak; an indistinct 
subterminal line is usually present. The hind-wings are pale 
bronzy-grey. The female is usually slightly larger and paler 
than the male, 
