File:A moss (Grimmia pulvinata), with "mystery jelly" - geograph.org.uk - 1182111.jpg

English: A moss (Grimmia pulvinata), with "mystery jelly". This moss, Grimmia pulvinata (Grey-cushioned Grimmia), is the most common Grimmia species in Britain, and its long silvery hair-points give the cushions of moss a furry, silvery appearance; these hair-points can be as long as the leaves from which they project.

It will often be found, as it was here, on top of a wall (in this case, a dry-stone wall). Its preferred habitat is on base-rich rock. The part of the wall on which it was growing is only a few metres from a pool (see 1178513, where the same wall is visible just behind the pool).

When in fruit, this species has capsules borne on long stalks (setae); however, these stalks are strongly curved when wet, so that the capsules are often partially buried among the leaves of the moss. However, the stalks become straighter with age.

As for the jelly in the image, the larger blob is 3 cm across. I put some under the microscope, but this substance was still largely a featureless gel; the few thread-like forms present appeared to be merely organic debris. This jelly is evidently not a living organism; see the link in the last paragraph for what I believe to be its origin.

See a BBC Scotland link – http://www.bbc.co.uk/scotland/outdoors/articles/jelly/index.shtml – for further information and for other suggested origins. As with many of the reported occurrences, this one was near a pool that is frequented by herons, and where frogspawn can be found; although there are various other natural "jellies" (for example, see https://www.geograph.org.uk/photo/1000481 ), the substance shown in this photo seems very similar to the gel that surrounds frogspawn. See Star jelly Richard Avery (d) 16:21, 16 January 2015 (UTC)

The jelly is sometimes found associated with clusters of tiny black rounded objects; for an example of this, see https://www.geograph.org.uk/photo/1560335