THE ENTOMOLOGIST. | 5) | 
of this insect, and I openly express my thanks to him on 
that account. This gentleman furnished me with sixty of 
these eggs, together with the female fly which had laid them. 
On the Sth July all the caterpillars appeared. Five or six 
days before the caterpillar comes out the egg begins to 
change colour only, and becomes dark brown at the place 
where the head of the caterpillar is, then again slowly brighter, 
and at last as clear as glass, so that the grub is seen in it most 
plainly; and I have pictured it at fig. 2, as it appears under 
a good magnifying-glass. Not less plainly is seen the move- 
ment of the dark spot under the head, which is the mouth of 
the caterpillar. The little animal is then trying to make a 
little hole in the top of the egg, and as soon as this is big 
enough for it to put its head through, the little caterpillar 
creeps out of it. Just after it is born it is of a yellow colour, 
with a dark brown head, and has a white horn bent forward 
on its tail, but this shortly afterwards becomes coal-black, 
and is split above on the point, or rather it has there two fine 
little points, which anyone who is sharp-sighted can see with 
the naked eye. This just-born fir-tree arrow-tail grub is 
shown at fig. 3. Most of these little caterpillars, after they 
are hatched, let the empty egg-shell lie, without making any 
further use of it; some, however, ate it up greedily; some 
even were not satisfied with their own egg-cover, but con- 
sumed also those of others. After consuming this breakfast 
the fir-tree needles are afterwards their special food, when, 
being still young, they feed in the manner aforesaid, like the 
caterpillar of the Anomalus fly (Fidonia Piniaria), in that they 
eat more at the edges of the spines, but afterwards, when they 
have become older and bigger, they eat them off cross-wise, 
beginning from above at the point and going thus down, 
leaving often a morsel of the spine at the foot. The growth of 
this caterpillar lasts above four weeks, within which time they 
moult four times, usually about every six or seven days: at 
each moult they eat up all the cast-off skins. After the first 
change the caterpillar appears striped with green, like fig. 4 
after the second and third moults the stripes become longer 
and more distinct, and the little horn still remains forked at 
the point, as is pictured at fig. 5, magnified; but after the 
fourth, or last change, the rosy stripe on the ‘back and the 
narrow black rings first come in sight. The little horn, 
