Oh, that's just the Black Oil aliens from X-Files. Don't let them touch you.

Could there have been a mole or something under the surface that died??? Doubt it....bet DBD is right....
If it were me, I would investigate....gotta know!!!....Do you have access to a hazmat suit?
Call OSHA....maybe they would let you borrow one.......and a tent. :o)

Sounds like some sort of stinkhorn fungus

LOL Webkat!
It does sound like some kind of stinkhorn. I've never seen this gelatinous mass filled with maggots before though. There is a good 2 cups worth of the stuff. That's a lot of flies! Also, I always figured that stinkhorns 'trick' flies into fertilizing. I didn't realize they also provided a growth medium for the the maggots.
I suppose that it is possible that something had died under the soil and a fungus grew out of the area. I haven't noticed anything that would resemble a bone or hair yet.

Has this mystery been solved yet??
Wondering.....inquiring minds HAVE to know! :0)

I have been unable to find a 'stinkhorn' that even remotely looks like my fungus. Furthermore, although stinkhorns attract flies, I haven't found anything that serves as a vegetable growth medium for maggots. The mystery endures, and it is driving me crazy. I have also tried harder to find bones, hair, or teeth that would indicate a dead animal and have found nothing.

Any pics?

I will take one this weekend.

Soooooo....where's the pic?

Hmmm, reminds me of the post "Hey, Larry, sorry no pic but what's this little brown moth?" LOL

ahahah ... well, I looked at it this weekend, and it was pretty much dried up. The maggots are either all dead or pupating. DBD - I hope maggot filled fungal expulsions aren't as commonplace as little brown moths where you live! lol

stinkhorn fungus, for pics go to Floridata (TM) and look at the November Gardener's Journal, full of pics and comments...LOL

Thank goodness! Mystery solved!

Here's the link. Jack is rather funny!

Here is a link that might be useful: fungus