BRITISH AXD EL'ROPEAX BUTTERFLIES AXD MOTHS. 



6i 



Genus Gastrofjacha, Ochs. 



The neuration varies somewhat, but in all 

 the discoidal cell is short, and one or more 

 nervures pass from the appendicular cell to 

 the costa. The females are usually larger and 

 stouter than the males. There are no ocelli. 

 The larvae are thinly covered with hair on the 

 back, and with longer hair on the sides. They 

 usually live on trees, some gregariously, and 

 the cocoon is dense or loose. 



G. crataegi, Linn. The Pale Oak Eggar. 

 Fore wings pale grey, with two black zigzag 

 transverse lines across the middle, enclosing a 

 dark grey band, and a brown dentated sub- 

 marginal Hne. The hind wings are lighter grey, 

 with a blackish central line. The fringes are 

 white on the nervures. The antennas have grey- 

 ish brown pectinations. The head and body are 

 reddish grey, thickly hairy. The moth is found 

 throughout Europe in August and September. 

 The larva varies much in colour and marking, 

 but is usually bluish black, thinly covered with 

 hair, with a white or yellowish transverse band 

 on each segment, between two red hairy 

 tubercles, and with a line of white spots on 

 each side. It feeds on whitethorn, willow, 

 sloe, oak, etc., in ]May and June. The pupa 

 is enclosed in a firm oval cocoon. Var. ariae, 

 Htibn. is larger and darker. It is only found 

 in mountainous districts. 



G. populi, Linn. The December Moth. 

 PI. XIX. fig. 4. is found from September to 

 December, according to the locality, being 

 widely distributed in Europe. The caterpillar 

 is short, with thin hair, dark grey, with large 

 black connected spots on the back, and four 

 yellowish warts on each segment. The belly 

 is flat, whitish yellow, with round cinnamon- 

 brown spots. It li\es on aspen, poplar, lime, 

 and oak, hiding in the cracks of the bark 

 during the daytime. 



G. franconica, W. Y. \Mngs dark brownish 

 grey in the male, thinly scaled, with darker 

 nervures and hind margins. Fore wings with 

 a straight pale yellow transverse line beyond 

 the middle, an indistinct line near the base, 

 and a black lunular streak in the centre. The 

 hind wings have an indistinct transverse stripe. 

 The fringes are yellowish. The female is larger, 

 reddish brown, with less distinct markings. 



Tlie antennae are brown, with a yellowish stalk, 

 and are strongly dentated in the male. In the 

 female they are only serrated. It is found 

 in the South of Europe in July and August. 

 The caterpillar is blue -black, with reddish 

 yellow hair, a blue dorsal stripe, and four fine 

 orange lines on each side. Below these is a 

 broader light blue line, irregular below, and 

 just above the legs a lighter reddish yellow 

 line. It lives gregariously in June and July on 

 couch-grass, chickweed, etc. 



G. castrensis, Linn. The Ground Lackey. 

 Fore wings pale yellow in the male, with two 

 brown central transverse lines, the interme- 

 diate space being darker. The inner transverse 

 line reaches along the inner border as far as 

 the base. In front of the hind margin is a 

 thinly dusted faint brown band, which does 

 not extend as far as the costa and inner 

 margin. The hind wings are brown, with an 

 indistinct yellow transverse line. In the female 

 the fore wings are brown, with two wa^■y 

 yellow transverse stripes. The antennae have 

 brown pectinations. The head and back are 

 yellow in the male, brown in the female. The 

 abdomen is darker. It appears in July and 

 August, and is widely distributed in Europe, 

 but is not usually abundant. The caterpillar 

 is orange on the back, with a white or blue 

 dorsal line bordered on both sides with black 

 spots, a blue lateral stripe, which is some- 

 times black, and blue incisions. The cater- 

 pillars feed gregariously on spurge, Centaurea, 

 Gemniitm, etc., and only disperse just before 

 pupation. 



G. neustria, Linn. The Lackey Moth. 

 PI. XIX. fig. 5. Larva 5a. Pupa 5b. is common 

 throughout Europe in June and July. The 

 larva; hibernate in a common web by hundreds, 

 and remain together till their last moult. They 

 feed on fruit trees, birch, oak, and sloe. The 

 larvae afterwards scatter, and are often very 

 injurious to the trees upon which they feed. 

 The chrysalis is enclosed in a soft whitish 

 mealy cocoon. The eggs are attached in rings 

 round the twigs. 



G. lanestris, Linn. The Small Eggar. 

 PI. XIX. fig. 6. is common throughout Europe 

 in early Sprmg. The larva; are uniform dark 

 grey. They then become dark blue, with two 

 hairv orange tubercles on each segment, be- 



