THE NATURALISTS’ JOURNAL. 
74 
by a number of little woolly yellow cocoons ! But memories are 
painful. Let us on. We will just glance at a few or my paper 
would not be complete. I have chosen the following:— Microgaster 
glomeratus , Pteromalus puparum, and Pimpla instigator , as typical 
species. 
Microgaster Glomeratus. —This is a very small insect measuring 
scarcely a quarter of an inch in expanse. In colour, it is black 
with fawn or ochreous coloured legs, the hinder thighs being black 
at the base and all the shanks and feet tipped with brown. An¬ 
tennae as long as the wings, which are iridiscent and contain a 
brownish spot on the fore ones. The insect by means of its 
ovipositor deposits eggs in various species of caterpillars. In 
this position the eggs hatch out into tiny white maggots which 
do not however at once make their exit from their larval host. 
No, they feed on the fatty substances of the viscera, carefully 
avoiding all vital parts, for should these be attacked or injured 
their own death would be quite as assured as the caterpillars. 
The caterpillar up to now has experienced no inconvenience, or 
at least it appears not to have done so, but the Ichneumon larvae 
have during this time arrived at their ecdysis and accordingly to 
undergo such they eat their way through the vital and other 
parts without discrimination and spin silky, yellow cocoons on 
and around its dead body, within which they complete their 
metamorphoses and in a few days appear as perfect imagoes. 
Pteromalus puparum. —Thousands of P. brassicoe fall victims to 
this indefatigable little worker as they do to the one just 
described. In this case the larval host generally reaches the 
pupal stage before its decease thus differing from M. glomeratus. 
The end is the same though with all of them and justifies the 
means. The larva rarely escapes. In P. puparum (see page 25) 
the sexes differ in appearance considerably. Thus the male is 
of a brilliant green colour and very glossy. The antennae long, 
and ochreous or tawny. The wings beautifully limpid. The legs 
bright orange, with the tips of feet in tinge black. The 
female on the other hand is greenish black, sometimes violet 
alone. The antennae are black, but tawny at the base. The 
legs are bright ochreous with intense black thighs except the 
base and tips. The four hinder shanks have the middle portion 
dark ochreous with tips of feet black. Expanse about 3^ lines. 
Pimpla instigator .—Handsome but evil smelling. This insect 
has an expanse of an inch. It is black ; the wings have a yellow¬ 
ish tinge with brown nervures and a stigma on fore pair. The legs 
are red, with the hips and hind feet quite black. Antennae long 
and slender. Ovipositor about half length of body; black 
and strong. The female lays a single egg in the pupa of P. bras- 
sicoe. It is hardly necessary to say that an imago of P. vistigator 
makes its appearance from the pupa and not P. brassicoe , this 
latter being nowhere in it, so to speak. From Midsummer to 
