Rhopalodia Study Sidetracked by Broken Pinnularia

[KurtM]

I started out with Rhopalodia as my object of interest, but ADD kicked in when a broken Pinnularia frustule seized my attention. I love broken diatom valves - where others may see imperfect specimens, it's a dissection in progress to me, and understanding morphology is of much interest here. Pinnularia is a lot like Rhopalodia: a thick form that tends to defy understanding of how it's built, in this case with its diagnostic "chambered" striae. So, far from imperfect, this specimen is very perfect indeed to me, and of exceeding interest.

I'm also playing around with stacking. The first image is an 18 image stack through the 40x/.65 with DIC, and the second a 20 image stack through the 100/1.25 lens with DIC and 1st order red compensator.

[btschumy]

Kurt,

I like your attitude about the broken diatoms. "When life gives you lemons, make lemonade."

[billben74]

I see your point.
I have a strew slide by Klaus which I bought with my 30 form in anticipation of my microscope purchase.
To be honest I didn't realise what strew meant in this context and was slightly dissapointed, but I will go back and investigate it with new eyes now.
I think there may be broken diatoms (and maybe some at different angles too...)
Many thanks.

[exmarine]

I understand the predicament were in concerning how to observe the girdle view of a broken diatom. How is the problem of turning the valve view on its side. I have seen a dissected diatom somewhere let me find it.

[rnabholz]

I have spent some time in the past looking at SEM images of pinnularia to try and get a handle on how they are put together, so anything that sheds light is welcome.

Very good images, really like the second.

[KurtM]

Billben74, your comments bring back memories of my first K. Kemp slides. Some of them were disappointing when I received them, but now, like magic, the very ones are right at the top of the list for interest. But I find it really not so unusual, as many diatom slides have a way of transforming themselves from ho-hum to holy-s**t!, as we accrue knowledge I suppose. At any rate, I have learned time and time again that it pays to revisit old slides, and this present little exercise is certainly no exception.

So again I thank, in proper order this time, those who started this current madness: Fan, for fishing out a rich Rhopalodia haul and sending it to Rod, Rod for converting the muck into diatom strew slides and imaging them, and you for making stacking comments on your thread that made me want to try new things with my own stacking.

Exmarine, I look forward to seeing what you come up with. In the meantime, there's a Micscape article on manipulating diatoms for alternate views (kinda hard to do on finished permanent slides):
http://www.microscopy-uk.org.uk/mag/ind ... atoms.html

Rod, let's go halvesies on a SEM...?

[exmarine]

I am sorry but for the life me I can not find the blessed format, but what I did find is a photo of a centric diatom. Sorry guys.