In this video I use optical sectioning to view different aspects of a testate amoeba. Starting at .06 in the video the advancing pseudopod becomes clearly evident. At .28 you can clearly see the body inside the shell along with various attachment points. From .43 to .48 you can see the texture of the shell (test) at various levels. The rest of the video follows the sections down again to the view of the pseudopod.
Here is a video of a fairly colorful tardigrade circumventing his little world of detritus looking for his next meal. Doesn't look like he found any and obviously has no concept that he may have traveled that path before.
The little fellow went for a nap (died?) after the video was taken which allowed me to take a number of stationary photos. This enabled me to stack a number of photos to get the whole image into focus.
I also managed a photo of his buccal apparatus which could help in IDing this specimen. So far we've only identified him to genus level; Genus Ramazzottius.
Yesterday I had found a, rare for me, Lacrymaria olor specimen and decided to move it to a clean slide for some imaging. I did manage to pick it up in a micro-pipette and transferred the water droplet to a new slide. A quick check with a low power objective confirmed it was still there so a cover slip was put on. Another quick search failed to locate it and a slow, methodical second look indicated why. It seems L. olor was swimming around in the water outside the cover slip. I washed it back into the jar so I could look for it another day.
Fast forward to today, I found 2 specimens from a different source. Go figure! Anyway, this time I made a video to put up. No feeding display, only searching.
Quite often we find odd little critters under the microscope lens that defy identification despite best efforts. Often they have added appendages or shortened features that just don't fit what the identification keys are leading you to. This has happened to me a few times when, after watching a video about centrifuges, I spun the samples at 4000 RPM as described in the video. Apparently this is a no-no and eukaryotes should never, if you value their well being, be spun at more than 800 RPM. Other injuries can be sustained when transferring specimens from jar to slide and then there is the always dangerous cover slip. In the following video is a peritrich that is stuck in some fibers that I thought might be loricated (encased in a shell) peritrich but was unable to ID with the keys available to me. An internet ciliate expert, Bruce Taylor, suggested that it might be a distressed member of the order Sessilida. That got me thinking about checking out that particular jar for similar specimens and the mystery was solved. This was a peritrich that looked like a type of vorticella that had its stalk and myoneme broken off.
This little fella had ingested a fairly long diatom but seemed to not want to, or be unable to, relinquish it despite it seeming to cause it some locomotion problems. In the past I had seen an amoeba let go of a long filamentous algae that it just couldn't envelope.
On April 21 of this year I posted a still image of some Peranemids using a darkfield oiled condenser and 50X oil objective. A few friends commented on a video I had made of the same group so I thought I'd post it now. It's a useful video for showing euglenid metaboly motion.
 | |||
| Codonella cratera, one of the few freshwater tintinnids |
 |
| Genus Spirostomum |
 |
| Unknown ciliate |
 |
| Heliozoan, possibly Actinosphaerium eichhorni |
 |
| This amoeba was dragging around a big diatom it had ingested |
In my last water sample from the La Salle river I was lucky enough to capture a number of Stentor coeruleus. These large bluish-purple Stentors can be spectacular when observed under a stereoscope with a higher power but the detail doesn't show up till you get them under a coverslip. With careful observation you can see the moniliform macronucleus, the oral ciliature and membranelles, cortical rows and the contractile vacuole.
 |
| Possibly Genus Litonotus |
 |
| Possibly Genus Pandorina |
 | |||||||||||||||||||||||||
| Synura |
 |
| Phacus |
I have witnessed this a number of time but have always lost the couple at the end when they seem to zoom off very quickly just as they divide. This time I seem to have caught them in the act of separating.
Deliberately selecting specimens to view under a microscope has always been a challenge for me...but I'm getting better! I thought I'd share my methodology in the hope that someone else can benefit from my experience. But before I get to the basics of what I do it's important to share that reading about techniques will only get you so far, you have to practice to get better. In my experience, the more you practice, the better you get.
There are two methods I employ, one involves a stereoscope, the other a microscope. My favorite method employs the stereoscope, an LED goose neck lamp and a watch glass. I add 5 to 6 ml of water to my watch glass, apply some side lighting with the LED lamp and start hunting for specimens. My zoom stereoscope can employ powers ranging from 7X to 180X by using various accessory lenses but I generally work in the 14X to 90X range to isolate specimens. First, using a higher power I dial in to a critter that I want to examine with the microscope. possibly clean away debris with a needle, and suck up the specimen using a micro-pipette (20 to 40 ul) with a rubber bulb. This is then transferred to another area of the watch glass and viewed to confirm a successful transfer. If unsuccessful, repeat. When you have the specimen in a water drop, transfer it to a slide, put on a cover slip and start viewing under the microscope.
For those that don't own a stereoscope a similar technique can be employed using your microscope. In this case, a small volume of water, perhaps a couple of ml, is picked up with a dropper or micro-pipette and ejected along the length of a slide. Your specimen is then searched for under a low power, say 4X or 5X, and once found treated just like the critter in the previous paragraph.
Bonus tips: Cover slips float and specimens like to attach themselves to the bottom of them. I use the illustrated tweezers to drop them and pick them up.
And stereoscopes can be as much fun to view protists as microscopes are. 3D and really fun to watch once you become familiar with what you're looking at.
 |
| Euglena |
One of the jars I had been sampling from all winter became
quite green. I took a fairly large sample from the mid jar water and
included some bottom sediment and ran it through the centrifuge at 800
RPM for about ten minutes. Out of the resulting pellet came a
significant number of algae, a large number of which were various
species of euglenids.
 |
| Phacus |
There are now reports of over 1500 species so identification for the layperson is almost impossible.
I also tried stacking a couple of the images with Picolay.
And here is the insect part, ostensibly from a bee. The piece is about 1/10 mm long.
After a long winter of limited access to fresh specimens, my river is again open, at least near the banks. However, the winter was an enlightening season since it taught me much about protist cultures, how to maintain them and how to sample them.
It all started last fall when I filled a standard “fish bowl” with water, mud and a few plants taken from the small river I live on. I began with a relatively large collection of microscopic specimens, including some larger types like gammarus, copepods, ostracods, fairy shrimp and daphnia. The bowl was placed in an east facing windowsill where it received direct morning light. This little micro environment provided a large number of critters for observation but after some time the plants died and things slowed down. Luckily I had a 30 gallon tank that had gone wild and in cleaning it up I was able to add a large matt of algae to my bowl, again rejuvenating it.
 |
| The fish bowl on the extreme left was the container that started it all |
It was at that point I started a jar collection, seeding them with soil, water and algae from the fish bowl. These jars were “fed” with dried oak leaves, dead grasses from under the snow, vegetable scraps and various grains, cereals or even garden dirt. Most of these jars developed in different ways and provided a source of interesting, but limited, species over the winter. Another jar collection was started in a north facing window with none getting direct light. I had noticed the jars on the sunny sill were getting quite warm on clear days.
 |
| My north facing jars |
One jar in which I was doing a Walstad experiment developed an algae explosion that I used to feed several of the jars with larger inhabitants. What I found interesting was that some of my best microbe sources were the smallest containers I used, old 35 mm film containers. I even had a population explosion of several ciliate species under a cover slip on a slide I was keeping in a “wet” container to watch the development of snail eggs.
After providing a winter of enjoyment under the microscope the jars will soon be emptied back into the river, cleaned up and readied for some new, springtime populations.
I went back to the water sample from yesterday's post with the intent of getting better pictures to help with identifying this little critter. After several attempts I gave up and went the video route. I've tried going through several keys to ID her but I appear to have little talent in this area. Specimen is about 250 um long.
If you have any ideas please post them in the comments. Ive been told by an expert this specimen belongs to the Order Ploima, and possibly (slight) to the Genus Proales.
I have a small 35 mm film tube that I put a grain of rice into as a food source to see what would show up. It turned out to be quite rich in species, mostly small algae, ciliates and flagellates. However there are a number of larger ciliates, likely Stylonychia, and what I assumed were flatworms. The mode of locomotion was very reminiscent of a ciliated protist. Wrong! I think. Yesterday I saw no evidence of a corona but today I did, a very small and unobtrusive one.
Yesterday I was able to count them in the dozens but today I found only a few but with a lot of oval cysts (or eggs). So I'm assuming they are cysts (or eggs) that were the result of yesterday's rotifers. Not sure what changed, maybe a dropping food supply or unfavourable water conditions. Several were quite lethargic and there were also a few dead ones laying around.
 |
| 35 um long, 20 wide, smaller than most bdelloid eggs |
I've been keeping a slide with some snail eggs in a "wet" container so I can watch the eggs develop over time. Over a couple of weeks nothing has happened to the eggs but we have a secondary event going on I found interesting. There was a population explosion of ciliates, and only one kind that I thought were Stylonichia. Along with these were a large number of cysts which I believed were associated with the ciliates.So now I believe I know what Stylonychia cysts look like.
This cyst (left image) was a stack of 7 photos to get the whole object into focus.
 |
| Genus Monoraphidium, idividuals are 14-21 um long |
 |
| Monoraphidium contortum, straight line length between tips is 18.4 um |
 | |||
| A few unidentified ones , small ones about 7um long and the raft of 4 about 10um long |
 |
| Genus Scenedesmus, 27 um long |
 |
| Unknown algae |
