WaTr.—Leaf-mining Insects of New Zealand. 481 
(20.) Agromyza flavopleura n. sp. (The Fern-fly).. 
The Imago. 
Male: Frons, antennae, palpi, proboscis, and genae lemon-yellow ; 
ocellar triangle and occiput black; arista pubescent, black; eyes dark 
red; each orbit with three bristles and a number of long fine hairs; ocellar 
bristles weaker than the post-verticals. 
Thorax black on dorsum, shining; pleura almost entirely lemon-yellow, 
two blackish spots, one on sternopleura and a smaller one above hind 
coxae; scutellum black, except at antero-lateral margins, where it is 
ellowish, as in adjoining part of thorax; anterior two pairs of dorso- 
centrals but little shorter than the two posterior pairs; about four 
irregular series of rather long setulae between dorso-centrals. 
Abdomen infuscated except at extreme base, and narrowly at extreme 
apex of each tergite ; under-surface yellowis 
Length, 3 mm. Female similar to male. - : 
Type in author’s collection; reared from mines obtained in Botanical 
Gardens, Dunedin. 
Distribution. : 
First found at Wellington, in the Botanical Gardens, 19th June, 1919 
(fairly plentiful), and has been taken in same locality from time to time 
si und also at Wanganui (scarce) and at Dunedin. Imagines best 
procured by rearing from mines, and will be found emerging throughout 
summer months till April. : 
Food-plants. 
Polypodium australe, P. Billardieri, Lomaria filiformis, Asplenium flac- 
cidum. 
Egg-laying and. Larva. 
Ova laid singly in minute pockets constructed beneath under-cuticle of 
leaves ; there appears to be no especially selected part. 
Full-grown larva when fully extended 6 mm. in length, just prior to 
pupating 3-5-4 mm., cylindrical, slightly expanded cephalad in region of 
third segment; light yellow, shining ; mandibular sclerite in each of the 
РЕВ 
slender, about опе and a half times the length of the mandibular sclerite. 
Length of pharyngeal skeleton, exclusive of mandibular sclerite—first instar, 
0-19 mm.; second instar, 0-29 mm.; third instar, 0-43 mm. Length of 
mandibular sclerite—first instar, 0-03 mm. ; second instar, 0-07 mm. ; third 
instar, 0-13 mm. Durations of stadia not known. 
The Mine. (Plate 39, fig. 3.) 
Under favourable conditions, a long, narrow, tortuous gallery. Margins 
fairly regular. Owing often to narrow fronds, gallery is so much involved 
‘to become in many cases, and especially in A. flaccidum, a blotch covering 
almost the entire leaflet. Constructed closer against lower cuticle than 
upper, but just as conspicuous on one side as other. Colour pale green, 
becoming white, generally slightly discoloured brownish in region of the 
pupa and at tips of leaflets. Frass dark green to black, very scanty, 
16—Trans. 
