Thursday, 27 February 2014

Orthotricha, stomata

After browsing Sam Bosanquet's piece on Orthotricha I was interested in observing stomata on the capsules of an Orthotrichum, out of curiosity apart from anything else. At the weekend I had seen one dissected, which I think was O.pulchellum, and I could see the immersed stoma which could be seen down a hole in amongst differently shaped cells which pointed the way to it like paving slabs around a small flowerbed.

Last night I carved up an Orthotrichum, and found several stomata around the base of the capsule principally (were they all below, and uncovered by, the calyptra? I now wonder).

This is what I came up with.

Same hole, different camera and lighting:

I think it's immersed because basically I can't see the stoma. It's inside that hole. I'm also embarassed to confess that I 'm not sure which species this is from although I suspect O.rivulare. This is doubly embarassing if true because it ought to be in my herbarium and not on the slab. Well, you live and learn. I still have a bit left so I can make sure. Now I think about it, it could have been diaphanum. Anyway, it shouldn't be too hard to pick up O.affine for comparison - it has superficial stomata.

Here's the link to the article: Bosanquet

New assistant

Too much material to process, so I'm training up a new assistant

Tuesday, 25 February 2014

Gallery M-P

Mnium hornum


Orthodontium lineare


Orthotrichum diaphanum

Cullaloe hills, March 2014

Plagiomnium rostratum

Plagiothecium undulatum

Cullaloe hills, March 2014

Pogonatum aloides

Polytrichum juniperum

Pterogonium gracile

Bryophyte apical cells

Last night while browsing Watson's "The Structure and Life of Bryophytes", I came across some information on the apical cells of mosses. There's a nice page on this here: link

The above link covers apical cells in all bryophytes, but the relationship of the apical cell shape to the final structure of the plant is fascinating, especially in the case of how it works in leafy liverworts.

I hadn't previously noticed this moss phyllotaxis before. Nor had I even heard the word! Lack of botanical background that I'm trying to redress currently.

Further info:
Wiki page on phyllotaxis
Harvard Morphology of Mosses

Monday, 24 February 2014

ENHS Bryo Workshop continued

So the second day of the workshop turned out to be a bit of a disaster. On arriving I found the park gate with a sign saying the park was closed - not good. One brave member of the troop was manning the gate though, so I made my way in to be greeted by the gatekeeper, who told me that (1) there was no electricity; (2) there would have to be a risk assessment; (3) if it was up to him he wouldn't let us in!

Down at the house the crew was assembling and we were finally able to make a morning of it at least. There was no going outside, with high winds and bits of fallen tree all over the place - some of them quite big. Making the best of it, what equipment we had with batteries (Liz's laptop and Rob's lamp) was put to good use as Liz gave a presentation on taxonomy and we examined a few pre-collected goodies.

At lunchtime we called it a day. We had already pressed the goodwill of the rangers a bit (thanks!). A few of us intended to take the cars outside the park and come back in for a walk since the weather was better. Unfortunately at that moment I found out that I had a flat tyre, and after replacing it with the "doughnut" from the boot I decided that discretion was the better part of valour and headed home. I would have liked to catch the other presentations too, and to check out the quarry - maybe next time. It was still an enjoyable and worthwhile experience, and probably one of those that everybody present will remember, at least in part because of the circumstances. A big thanks to everybody who made this weekend work.

Here are a selection of shots from the weekend.

First up, a favourite of mine - Hypnum cupressiforme

The longitudinally-creased Eurhynchium striatum

A species I had an unexamined sample of at home from Water of Leith, Dichodontium pellucidum

The always tricky (but hopefully less so with experience), Ceratodon purpureus

Leaf sections of P.formosum, expertly cut by Julie. My own attempts not shown for fear of embarassment.

The leaf-breaking Dicranum tauricum again

The terminal tooth on the nerve of Cirriphyllum crassinervium (slide prepared and feature located by Liz)