I get the impression that the inside consists of a whiteish central bit within a jelly-like layer. If that impression is correct than this would be some immature stinkhorn, but at this stage I cannot tell you even the genus. Are you able to collect some with some of the surrounding soil/mulch/twig litter. If so, you could try keeping them in a shallow saucer with a little water (just enough to keep the soil/mulch/litter damp) and wait to see if they open up for you to reveal exactly what they are. I’ve done that with some immature stinkhorns. Depending on how advanced these are, you may need to wait a day or two – and of course, there’s still the possibility that any further development stops.