Odd organism on Rhizomnium

These yellow, gemmae-like structures were found directly attached to a protonemal mat of what I assume was Rhizomnium punctatum. I've really struggled to even identify the phlyum of the organism and have wondered if they might even be galls. There are multiple  growths all similar in character and have kept their shape and colour even after being in the dry state for 10 days or more. Any help in identifying them would be greatly appreciated.

1. Structure of growths on decorticated wood.

2. Cross section through one of the growths showing that they are attached to the moss rather than the substrate.

3. Growth with multicellular propagules and protonema

4. Propagules - NB minor tick marks 2.5 μm