I have this moss terrarium that is not doing that well. It’s never done well. I guess moss doesn’t really want to live in a jar. Probably more than a year ago, I dropped a maidenhair fern frond in there that was loaded with spores. I thought it might sprout, but after the leaf decayed, nothing happened so I forgot about it… not that I really knew what fern sprouts looked like. Months ago, I started seeing this strange structure growing out of my dying moss clumps. It kind of looks like tiny kelp. I thought maybe it was a liverwort or some moss structure that grows from moss in some last attempt to live. My “moss kelp” eventually grew some branches, so I thought it was making spores.
Fast forward to today. My maidenhair fern in my office (a division of the one mentioned earlier) is dropping spores all over the window sill, so I did some internet research on how to grow ferns from spores. That’s when I discovered I’ve actually already done it. The “moss kelp” is the prothallium or the gametophyte of the fern (the structure where fertilization happens). From the prothallium, the fern that we recognize grows. Now I wonder if I can do it again on purpose.
A note on the photograph: photographing prothallia is really difficult. I was frustrated at the lack of good photos online, but now I understand, so please excuse my lack of detail in my photo. I may try to get some better macro photos later.