[Tom Netall]

Found a lot of these batches of yellow eggs in the shed, and many have a caterpillar attached.

At first it looked as if the caterpillars had laid the eggs, but that's daft.

Anyway, on closer inspection of the one pictured in the attachment, the caterpillar appears to be being devoured by the emerging grubs.

What are they? Do I leave em alone ?

[lovemyveg]

Found a lot of these batches of yellow eggs in the shed, and many have a caterpillar attached.

At first it looked as if the caterpillars had laid the eggs, but that's daft.

Anyway, on closer inspection of the one pictured in the attachment, the caterpillar appears to be being devoured by the emerging grubs.

What are they? Do I leave em alone ?

Could they be fly's eggs and it is the maggots that are devouring the caterpillar?

[Tom Netall]

That's just it, I don't know     But thanks, any ideas are welcome.

[pushrod]

Maybe one of those wasps that provide a meal for the emerging grubs



are the grubs emerging from the caterpillar? (can't quite see from pic) if so they are from the caterpillar wasp.

[Tom Netall]

Maybe one of those wasps that provide a meal for the emerging grubs



are the grubs emerging from the caterpillar? (can't quite see from pic) if so they are from the caterpillar wasp.

Caterpillar wasp eh, that's interesting.

It looks like the grubs are emerging from the eggs and then eating the caterpillar.

I think I'd better stop squashing em 

[8doubles]

Ichneumon wasps are the culprits they inject their eggs into the newly hatched caterpillar which keeps growing and when it goes to pupate the wasp larva break out and make the cocoons you saw.
Them and the proper wasps have been doing a grand job on the caterpillars on my broccoli all summer.

[titch]

i took some caterpillars from my brussels into pre-school for the children to look at.
they too produced these eggs - confused i looked it up on the internet

they are the wasp eggs you mention 8 doubles by golly they are clever.
the grubs burrow into the caterpillar brain before hatching and change its behaviour.  When they bust out of the caterpillar, the caterpillar spins the silk around them and will stay close, protecting them for up to 6 days, they no longer eat, and eventually die

isnt nature amazing
it also said not to squish the wasp larvae cos they wont eat your plants but will rpoduce more wasps who will in turn sort out the caterpillars

the older children at breakfast club have been fascinated by this - amazing  stuff you have to admit

[Tom Netall]

Ichneumon wasps are the culprits they inject their eggs into the newly hatched caterpillar which keeps growing and when it goes to pupate the wasp larva break out and make the cocoons you saw.
Them and the proper wasps have been doing a grand job on the caterpillars on my broccoli all summer.

Cheers 8doubles. That's the one, just googled it.

Unbelievably, they even avoid eating the vital organs of the host caterpillar so as not to kill it too soon.