Maidenhair Pocket-moss

I found this one growing on the rock face beside the burn at Auchtertool.  It had a general look of Fissidens, with the little flat hands poking out.

At home, I consulted the books. Watson describes the leaves of Fissidens as having a peculiar form not found in other mosses.  The leaf has a boat-shaped clasping portion, with a wing of tissue extending beyond that.  The nerve goes out into this wing.

I saw this under the microscope and had fun trying to capture a picture:

One of these days I’ll get the hang of taking photos down the microscope.

Here’s why I think it’s probably Adianthoides.  Reasoning all my own, so quite likely to be wrong.

I discounted some Fissidens species because of their size or the absence of any records nearby.

The nerve runs up to the tip of the leaf but no further, and the shoots are short and compact, so not Taxifolius.

There is a pale edge to the leaves, but under the microscope it’s clear that this isn’t a margin, just a couple of rows of cells with the same shape as the rest but less colour.  So not Bryoides, which has leaves bordered  by long, narrow cells.  (I also looked for the bud-like male organs in the leaf axils, and didn’t see any.)

The leaves are minutely toothed.

So I’m going with Fissidens adianthoides for now.

Found at Auchtertool.