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stems, and managed to get about a dozen, some of which duly produced 
imagines. Since then several facts have been accumulated, of which 
the following appear to be among the most interesting. 
Ovum : The ovum is about |mra. in diameter, round, whitish, and 
quite devoid of markings, becoming darker before hatching, when the 
pinkish segments of the young larva can be seen through the shell. 
The eggs are laid in the centre of old rush stems, and the way they are 
placed there is most interesting. The 2 possesses two sharp spines on 
the last segment (see plate), with which she makes a longitudinal slit in 
the stem ; the spines are then forced apart, whilst the ovipositor is thrust 
between them into the pith, and the eggs are deposited in bunches of 
three to eight. The ovipositor and spines are then withdrawn, and 
the cut closes, and is hardly to be seen without a lens. The eggs 
were laid from July 20th to August 1st, and began to hatch about 
August 10th. 
Larva: When first hatched, about 3|mm. long; shining creamy- 
white; head, thoracic plate, and anal-plate, blackish-brown; meso- 
and metathoracic segments rather flattened, and pinky-white in colour, 
other segments rather raised and pinky-brown, giving the larva a rather 
banded appearance, the body having a few hairs arising from tubercles ; 
true legs slightly dark at tip; ventral surface and legs whitish. The 
full fed larva examined on June 3rd, 1908, measured about 16mm. 
long; bead yellow-brown; prothorax and anal segments with straw- 
coloured, shining plate ; colour of body pinkish-white, ventral surface 
dirty-white ; head and body emitting some small whitish bristles; 
segments bearing also thirteen to fourteen small blackish tubercles. 
The thoracic segments are rather flattened, rest swollen, anal segment 
flattened, true legs yellowish, prolegs dirty-white, dorsal line whitish. 
Habits of larva: 'The young larvae remain in the old stems, 
making galleries in the pith towards the root, nnd keep more or less 
together. They appear to hybernate in these old stems and early in 
the spring bite their way out, when each one enters a growing stem. 
The larvae appear to feed in several stems. They bite an oval-shaped 
hole about a quarter of they way up the stem, and, entering, feed head 
downwards, ejecting frass through the hole ; on reaching the root they 
eat their way out, and enter another stem. The infested stems 
quickly turn yellowish-green and wither. The ejected frass can be 
seen on the moss, etc., round the tufts of rushes, and a little searching 
reveals the infested stem. When about to pupate the larva enters an 
old stem low down just where the sheath ends, beneath the mossy 
surface of the fen, eats out a chamber, leaving a thin skin over its 
emergence hole, which is just on the fen surface, and pupates head 
upwards. They are fullfed from the end of May to the middle of 
June. The food-plant is Jmiens laniprocarjms. Mr. ISankes believes it 
feeds in J miens ejt nsus in his district, and it may feed in some of the 
other J uncus species also. 
Tuba: ll^mm. long, with a distinct “beak;” anal end of pupa 
rounded, with dorsal surface ending in two sharp spines; colour light 
brown, segments slightly darker, also the ocellar area (beneath glazed 
eye). 
Habits of imago: The imago flies just before dark, and the flight 
is straight and just above the herbage; they frequently settle, and if 
xix. 
