
XVIT.—THE 
Genus 1—ELACHISTA, Treitsch. 
An extensive genus, widely distributed but principally 
known from Europe; the species are often overlooked. Larvae 
mining in grasses. 
We have eight species in New Zealand. One is re- 
stricted to the North Island; three to the South Island, 
and four occur in both islands. 
ELACHISTA ARCHAEONOMA. 
(Elachista archaeonoma, Meyr., Trans. N.Z. Inst., xxi., 179.) 
(Plate: XX Vili ict Sie a LOO) 
Except in the extreme south this very active little 
insect is common and generally distributed throughout the 
eountry. 13 
The expansion of the wings is about five-sixteenths of an 
inch. The fore-wings of the male are dark grey densely spec- 
kled with paler grey; there are two dull white marks a little 
before the middle followed by two blackish spots placed on the 
costa and dorsum and a blackish streak in the disc; there is a 
marginal series of black dots. The hind-wings are dark grey. 
In the female the fore-wings are white sprinkled with brown 
from the base to beyond 4; there is a large blackish-brown blotch 
near the middle and a smaller blotch at the apex, the two being 
connected by a slender line in the disc; a number of large 
black seales is situated on the cilia. The hind-wings are very 
pale grey. 
The perfect insect appears from August till March, 
occasional stragglers being met with on fine sunny days 
as late as June or July. It is often abundant in grassy 
places, and is very fond of the afternoon sunshine, when it 
may be seen running about on the blades of the grass, and 
taking wing with great agility. Pairing takes place to- 
wards sunset. 
ELACHISTA OMBRODOCA. 
(Blachista ombrodoca, Meyr., Trans. N.Z. Inst., xxi., 179.) 
(Plate XXXVIIL., fig. 4 ¢@.) 
This little insect has occurred commonly at Christ- 
church, Dunedin and Invercargill. 
The expansion of the wings is slightly over 4 inch. The 
fore-wings are pale grey (darker in the female) with two 
obscure whitish transverse bands near the middle (plainer in 
the female); there is an obscure black streak on the fold; two 
short longitudinal streaks near the middle of the costa and 
dorsum respectively and a rather long streak at the apex; the 
entire wing is thinly strewn with a few black scales. The 
cilia are grey with a few black scales. The hind-wings are 
grey. ‘ 
The perfect insect appears from September till March, 
and is found on open grassy places, roadsides, ete., where 
it is often very common. 
ELACHISTA EXAULA. 
(Elachista exdula, Meyr., Trans. N.Z. Inst., xxi., 178; Hlachista 
watti, Philp, ib. lv., 213.) 
(Plate XLVII., fig. 3 4; Plate XXVIII., fig. 15 @ variety.) 
This delicate-looking little species has occurred in the 
North Island on Mount Ruapehu and on the hills on the 
eastern side of Wellington Harbour. In the South Island 
it has been found on Mount Arthur and on the banks of 
the Mataura River. 
TINEIDAE. 319 
The expansion of the wings is five-sixteenths of an inch. 
The fore-wings are elliptical, cream-coloured, very finely speckled 
with darker; there is a chain of minute black dots along the 
basal portion of the fold; a small cluster at the end of the fold 
and another rather irregular chain of minute black dots before 
the apex. The hind-wings and all the cilia are grey. 
A remarkable variety of this species having the apical 
three-fifths of the fore-wings clouded with grey is depicted on 
Plate XXVIII., fig. 15. Another form, haying the usual black 
markings on the fore-wings absent, has been described by Mr. 
Philpott as a distinct species, under the name of Hlachista 
watti. 
The perfect insect appears in September and March, 
flying freely amongst grass in the afternoon sunshine. | 
ELACHISTA HELONOMA. 
(Elachista helonoma, Meyr., Trans. N.Z. Inst., xxi., 178.) 
(Plate XXVIII., fig. 14.) 
This neat-looking little species is common on the Port 
Hills near Christchurch. 
The expansion of the wings is slightly over + inch. The 
fore-wings are pale whitish-ochreous speckled with numerous 
blackish dots; there is a dense chain of larger dots forming a 
streak from the base to about 4 and another streak from above 
this to the apex; the dots are also more numerous on the dor- 
sum. The hind-wings are greyish-ochreous. j 
The perfect insect appears from January till March, 
and is abundant amongst tussock grass to which it appears 
attached. 
Described and figured from a specimen in the Fereday 
collection. 
ELACHISTA THALLOPHORA. 
(Elachista thallophora, Meyr., Trans. N.Z. Inst., xxi., 178.) 
(Plate XaLVI., fis. 12) 4.) , 
This very narrow-winged species has occurred at Wai- 
ouru, Paekakariki and Wellington in the North Island, 
and at Mount Arthur, Christchurch, and Dunedin in the 
South Island. 
The expansion of the wings is about seven-sixteenths of an 
inch. The fore-wings are very narrow with the apex acutely- 
pointed; dark greyish-ochreous; there is a very fine longitudinal 
white streak slightly above the middle and a much broader 
streak below the middle. The hind-wings are narrow, with the 
apex extremely acute; greyish-ochreous. 
The perfect insect appears from November till Febru- 
ary. It is found in grassy places, but is extremely local. 
Mr. Meyrick points out that the variation in size is note- 
worthy, some of the largest females being twice as large 
as the males. The species is a remarkably distinct one, 
but recalls H. rufocinerea, to which it has probably some 
real relationship. 
ELACHISTA GERASMIA. 
(Elachista gerasmia, Meyr., Trans. N.Z. Inst., xxi., 177.) 
(Plate XXVIII., fig. 11.) 
This pretty species has occurred at Auckland, Hamil- 
ton, Makotuku, Ida Valley, Lake Wakatipu, and Inver- 
eargill. 
The expansion of the wings varies from considerably under 
to slightly over 4 inch. The fore-wings, which have the costa 
rather strongly arched and the apex acute, are greyish-white, 

