Rotifer video and other odds and sods

The yard is again blanketed in snow, temperatures near freezing and I'm questioning why my father chose to stop here on his way to settle in the Gulf Islands. Although I remain dubious, some are suggesting summer may actually arrive this year. At least I had the foresight to gather some specimens after a too short balmy interlude. So let's take a look at what my intrusion into the freezing waters of a roadside ditch actually uncovered. No image because it was zooming but I saw my first Gastrotrich. Pretty cool little creature and very distinctive. And a bunch of other stuff!

This appears to be an ostracod, a bi-valve that feeds on detritus...at least that's where I found them. I saw a number of different sizes but they all seemed to look alike. I found one "dead" individual but it seemed just like an empty shell with the outline of the innards inside. Although it seems unlikely, I wonder if they molt? Then again, that would account for all the different sizes.

I saw only a few diatoms but I think this is a new one to me...not the usual pennate diatoms.

This might be a type of flagellate colony and unfortunately I couldn't see any detail beyond what is shown in the image. What I did observe was that water was being pulled towards it, very similar to what a rotifer or vorticella might do. The whole bunch was only about 10 microns across.

A ciliate, possibly a hypotrich but I may be getting beyond my abilities here. Kind of neat anyway and a new one for me. :)

Another ciliate, again possibly a hypotrich. Again, I may be wrong.

Not sure what I have here, perhaps a flagellate or a planktonic alga, perhaps a Micractinium. Or perhaps not.

No idea here but it did look different.

I think I've seen one of these before but am still as unsure as I was before about its identity.

A couple of flagellates that were swimming around rather slowly may be Euglena.

Another unknown ciliate, perhaps another hypotrich. There appear to be cirri, fused cilia that act as one unit, both anteriorly and posteriorly. Are these last two utterances even words?

Cyclopian garment change...

Cyclops reluctantly assumed a side pose for the camera

Spring has made a tentative approach but is in steady retreat again...temps are heading down to freezing again later today. The warm weather of the last few days did however open a ditch along my property and I've finally got a whole bunch of stuff to examine. Cyclops, ostracods, and a whole bunch of different ciliates with many rotifers among them. My technique, if I can call it that, was to open a jar at the bottom of the ditch, right above the sediment. Doing this allowed a bunch of water to rush into the container bringing everything within a few inches into it, including some debris. back at the microscope, one micro-event did stand out. As I was examining one of the copepods, it started to molt and in just a few seconds it was out of it's old skin and motoring away. Luckily, I had been taking pictures and I got a couple of, well, mediocre images that show what happened. I wonder if the event was serendipitous or the molt was brought on by the pressure of the cover glass?

Bubble on upper back shows where old skin has started bunching up

Discarded skin on left, newly clothed cyclops on the right

Books that instruct and entertain...me anyway

This book, published in 1960, will fit right in with those of us using microscope models sold during that era. It is based on a course delivered by the author and designed for students and hobbyists. Is there anyone reading this blog who doesn't fall into one of those categories?

 A great contemporary book for those interested in taking pictures through the microscope. The author understands his subject and has done a good job of transcribing that knowledge to the pages of this book. He is also known to frequent one of the Yahoo microscope groups where he helps with questions and posts about his hobby.

 The best book I've found to help decipher the identity of those unknown critters found in many drops of water. It's set up as a key for protozoa with ample photos and drawings to help with the ID.

 Another great book, and the title says it all. A mixture of technical information and essays on observations that will be both helpful and enjoyable. The book is no longer in print and demand has pushed the price of used copies far beyond the original price. I love what the internet has done to book accessibility but hate what it's done to prices.

This is an eBook about a comprehensive protozoan study in a small bog area of Germany. The book is filled with photos and is a
available online for a reasonable amount.

















And then there is a whole treasure of books that are no longer copyrighted and freely available for download. Many of these are extremely relevant to what we're doing at the microscope today, in addition to being well written in a somewhat archaic tone. Most are littered with hand drawn illustartions. Here are three that I'm reading right now.

 Common Objects of Microscopes

 Evenings at the Microscope.

 Half Hours with the Microscope.

DIY scanning microscope...

I've tried using my Zeiss Universal to scan for specimens in a petri dish but the stage was NOT designed for that. After flipping the dish onto the floor once and other times balancing it while trying to stay in focus I had had enough. Yesterday, while mixing a cool beverage with watching my wife rake the lawn, the fermenting idea coalesced into a solid plan. After supper I hit the machine shop and started milling a couple of discs; one out of aluminum, the other plastic. Held together with some thin, double-sided tape and a couple of screws, it fit perfectly into the existing stage housing. And I was now able to slide around a petri dish to my heart's content, just like the old days with my student microscope.











 Due to lack of clarity on my part, I've been asked for additional photos to explain my device. In response, I offer the following:

Here is a photo of the original stage in place, complete with all paraphernalia that allows manipulating a slide using geared mechanical movement in the X and Y direction. Unfortunately, it is less friendly when trying to scan a petri dish.

Pictured here is the stage base, with stage removed. The three contact points are evident; two in the back and a spring-loaded one at the front. The new flat stage is designed to lock into these same three contact points.

And here is the finished product, a flat, unobstructed surface. The petri dish is moved around until a victim is isolated under the objective. The water, including said victim, is then drawn up into a pipette and deposited elsewhere in the dish or onto a slide .

Mite I find an adult or another egg?

 The mite of the previous post had piqued my interest and I was anxious to learn more. A search of the internet failed to provide any new information so it was back to the sample for either an adult or another egg. No adults but I did find another egg, this one intact and still containing what appears to be a fully formed specimen. The shot to the left is focused on the hairy fringe which seems to cover the whole egg. Four legs are evident near the bottom of the egg and a dark area might indicate where the head is located.

Here is another area of focus, this time nearer to the upper, outer surface.

At this point something odd happened that I just didn't catch while viewing through the microscope. Either some debris floated up to the egg or the evaporating water brought some debris closer to the egg. In either case, the bottom-right area of the egg was covered with small living organisms, as shown in the image to the right. There were two sizes of circular visitors, the small ones easily seen in the image and some much smaller. No idea what they are but the smaller ones might have been bacteria size. Or did the pressure of the cover slip due to receding water cause the egg to break?

Here is a darkfield shot of the scene showing the general mayhem surrounding the egg. The whole field to the bottom right of the egg is a mass of moving things, for want of a better word. I wish I had recorded more of what happened and other details like magnification.

A mite fuzzy...

I ran into an interesting experience yesterday while strolling down the microbial highway. There, not more than 10 inches away, I saw what appeared to be a new born mite struggling to get out of its egg case. Camera always at the ready, I snapped a photo so the scene details could be shared with you. The emerging mite appeared to be about 30 microns wide.

A few things were working against me. This egg, if that’s what it actually was, came from some tree lichen so the little beasty may have been terrestrial in nature. Since it was immersed in water as part of my plan to capture the elusive water bear, it may have been experiencing some distress. I was also having trouble with image focus; perhaps the mite was too thick or opaque for proper focus or illumination. It also seemed to be completely covered with a fairly thick layer of bacteria, caught in the image as a lighter halo surrounding the emerging mite and egg . When the shutter closed, only the upper two legs seemed to be in focus. So there we have it...poor picture but an interesting event I wanted to share. 

After this was all over the little critter was transferred to a drier piece of moss in the hope it may successfully continue its passage to eventual adulthood.

Another visit with the 8 form test diatoms...

This feels like self-flagellation given the state of my camera setup but I just had to see what my 100X objective would do with these diatoms. I had read a number of articles on this exact subject on the Microscopy-UK website and the results others were getting were, to say the least, tantalizing. Since I normally use the 0.63 NA condenser, I removed it and put in a 1.40 NA condenser.  A drop of immersion oil on the condenser, lower the slide onto it, another drop on the slide, move the 100X/1.30 oil objective onto the slide and I was away. The filter tray had a green filter and the condenser and aperture diaphragm were adjusted for maximum light and the BF hole of the turret was set slightly off center to provide a bit of oblique illumination. The view, once I got it into focus (no small chore for me at this magnification), was a level beyond what I had experienced before. I saw obvious detail in the 7 diatoms with the largest striae intervals and if I squinted, and held my tongue the right way, I could even see the lines in Amphipleura pellucida. Of course, this detail wasn't present in the images but if you've been following this blog you know why. But I've gotta say, I'm pretty happy with the results after a bit of Elements work in removing the color and sharpening. The magnification of the following images is not constant.

Amphipleura pellucida  .27 microns... if you stare REAL hard you can see the lines

Frustulia rhomboides  .30 microns

Pleurosigma angulatum  .525 microns

Surirella gemma  .50 microns

Nitzschia sigma  .44 microns

Stauroneis phoenicentron  .72 microns

Navicula lyra  1.25 microns

Gyrosigma balticum  .67 microns