Apparently the ichneumon fly (Ophion obscurum), and not the true sawfly, is meant.
The ichneumon fly as well has been watched, and all its wicked acts recorded.
The eggs of the ichneumon fly hatch first and feed upon the eggs of the spider.
And then comes some secondary parasite, some ichneumon fly, and lays an egg within this grub, and behold!
It was hanging from a thread, down which the ichneumon fly was seen to crawl.
There are two species of spiders and a species of ichneumon fly that destroy them.
So first he sneaked in here and put an ichneumon fly in my breeding-cage.
The ichneumon fly, Fig. 103, is such a parasite; it destroys millions of insect pests.
I examined numbers of them, and found the scarlet egg of the ichneumon fly under many of the shards.