October 2012 - MicrobeHunter.com

Microbe
Hunter
Microscopy Magazine
ISSN 2220-4962 (Print)
ISSN 2220-4970 (Online)
Volume 2, Number 10
October 2012
The Magazine for the
Enthusiast Microscopist
http://www.microbehunter.com
Focus Stacking with
Video Frames
Gram Staining
Testing an
Educational
Microscope
Plant Leaves
Staurodesmus tumidus
Focus Stacking Plant Leaves Desmids
MicrobeHunter Microscopy Magazine - October 2012 - 1

ABOUT
Microbehunter Microscopy Magazine
The magazine for the enthusiast microscopist
MicrobeHunter Magazine is a non-commercial project.
Volume 2, Number 10, October 2012
ISSN 2220-4962 (Print)
ISSN 2220-4970 (Online)
Download: Microbehunter Microscopy Magazine can be downloaded
at: http://www.microbehunter.com
Print version: The printed version can be ordered at:
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Publisher and editor:
Oliver Kim, Ziegeleistr. 10-3, A-4490 St.Florian, Austria
Email: editor@microbehunter.com
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Tel.: +43 680 2115051
Images and Articles by:
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Oliver Kim, Luca Monzo, R. Nassar, Mike Guwak.
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Front Cover:
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Left image: R. Nassar
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2 - MicrobeHunter Microscopy Magazine - October 2012

CONTENTS
4 Focus Stacking with Video Frames
A method for obtaining a rapid focus stack from a
slowly moving amoeba under the microscope.
R. Nassar
4
6 Some Thoughts on Gram Staining
Gram staining is a quite powerful staining technique,
but requires careful standardization of the bacterial
culture.
Oliver Kim
8 Testing a Low-cost Educational Microscope
Yes, there are some low-cost microscopes around,
which do perform.
Oliver Kim
8
12 Observing Plant Leaves
Clear nail polish can be used to make impressions of
plant leaves.
Oliver Kim
17 Staurodesmus tumidus
Mike Guwak
19 Gallery
Images by Luca Monzo
12
17
22
Answer to the puzzle (back cover):
Plant leaf
MicrobeHunter Microscopy Magazine - October 2012 - 3

Technique
Focus Stacking
A method for obtaining a rapid focus stack from a slowly moving amoeba
under the microscope.
R. Nassar
In astronomy, image stacking is used
to make faint stars visible by adding
(or averaging) several images in
order to increase signal-to-noise ratio
[1]. In macro photography and photomicrography,
depth of field is extremely
limited, and image stacking is used to
combine several images (in the form of
a focus stack) that are focused on the
subject at different depths in order to get
the whole subject in focus.
A stack of still images can be used
when the subject is stationary. For a
slowly moving subject, video stacking
has been used where frames from a
video clip are extracted and the resulting
images are stacked [2,3,4,5].
1
I wanted to get images of an amoeba
for a focus stack. But even an amoeba's
very slow movement was too fast for a
stack of still images: recording one image,
then refocusing the microscope by
a few micrometers and repeating the
procedure took too long. In this case I
used a video stack by focusing the microscope
sufficiently quickly while recording
a video clip. I set the
microscope focus well below the bottom
of the amoeba and, using the coarse
focus knob, focused rapidly well beyond
the top. This ensured that the
zones of acceleration and deceleration
of the microscope stage occurred outside
the range of focus of interest and
that the focusing speed was nearly constant
when any parts of the amoeba
were in focus, thus ensuring approximately
equally spaced planes of focus
of the successive video frames. I then
picked several successive frames (in
this case 8) that spanned the depth of the
amoeba and stacked them using CombineZP.
At the video rate of 30 frames/s,
the 8 frames would have been recorded
in about 1/3 second, fast enough for a
slow-moving amoeba. A slightly slower
movement of the stage during focusing
would have allowed me to obtain
more images for the stack at smaller
Figure 1: The resulting stack is
shown below.
4 - MicrobeHunter Microscopy Magazine - October 2012

Focus Stacking
Technique
2
6
3
7
4
8
5
9
Figure 2-9: The individual video frames used to make the stack.
MicrobeHunter Microscopy Magazine - October 2012 - 5

Technique
Gram Staining
distance increments, but would have
taken longer and risked more movement
of the amoeba between the individual
images and possible difficulty in obtaining
a good stack. If you try this method,
please make sure that you are focusing
in a direction of increasing the distance
between the objective and the slide in
order to avoid colliding them together
accidentally and possibly causing severe
damage to the objective. The eight
video frames comprising the stack are
shown in figures 2-9.
■
References
1. Wikipedia. "Speckle imaging". http://en.wikipedia.org/wiki/Speckle_imaging.
2. Walker, D. Video microscopy trials with the USB Live View output of a DLSR camera. Micscape
Magazine, June 2008.
3. Cypionka, H. Videostacking.
http://www.mikroskopie.de/mikforum/read.php?2,48956,48956#msg-48956, July 26, 2008.
4. Cypionka, H. Videostacking.
http://www.mikroskopie-forum.de/index.php?topic=9190.0
May 18, 2011.
5. Krebs, C. Netzelia, testate amoeba, ingesting alga.
http://www.photomacrography.net/forum/viewtopic.php?t=15584
January 01, 2012.
Gram staining is a quite powerful staining technique, but requires careful standardization
of the bacterial culture.
Oliver Kim
Gram staining is one of the most
well-known staining procedures
for bacteria. It was discovered
by the Danish scientist Hans
Christian Gram (1850–1938). Gram accidentally
discovered this staining procedure
while he was working with Carl
Fiedländer (who discovered the bacterial
cause of pneumonia in 1882).
Gram staining allows for the differentiation
of bacteria in to Gram positive
and Gram negative bacteria. The Gram
positive bacteria stain dark blue or purple,
while the Gram negative bacteria
display a red color. The staining properties
are due to the properties of the cell
wall. Gram positive bacteria have a
thick cell wall, which is able to retain
the blue-black color complexes inside
the cell. The Gram negative bacteria
have a much thinner cell wall, which
allows the complexes to be washed out
by alcohol. For this reason, the Gram
stain was for many years a central technique
in bacterial identification. While
molecular techniques have largely taken
over the identification process, Gram
staining remains a popular technique for
microbiological education.
In his 1884 publication, Gram described
the method as a means to selectively
stain pneumonia bacteria of lung
tissue sections. The surrounding lung
tissue was not stained, making the bacteria
much easier to locate. In his publication
from 1884, he states the
advantage of this staining procedure:
“In my procedure the nucleus and other
tissue elements remain unstained, while
the cocci are strongly stained. This makes
them much easier to locate than previously,
since in ordinary preparations from
pneumonia patients, where such a large
amount of exudate occurs, they are impossible
to see.”
Figure 1: Gram stain of Staphylococcus
aureus (Gram positive cocci),
staining blue-purple and Escherichia
coli (Gram negative bacilli), staining
red from the safranin counter-stain.
Image credit: Creative Commons by Y tambe.
6 - MicrobeHunter Microscopy Magazine - October 2012

Gram Staining
Technique
The procedure
The bacteria are taken either from a
liquid culture or agar medium. Christian
Gram took the samples directly from
lung tissue. The bacteria are then
smeared on a microscope slide, airdried
and heat-fixed. For heat-fixing,
the slide is pulled 2 times through the
flame of a Bunsen burner, with the sample
pointing away from the flame. This
process "bakes" the bacteria to the glass
slide and prevents them from being
washed away during the staining process.
The primary stain crystal violet is
then applied to the fixed bacteria for 1-3
minutes. Gram's iodine solution is then
added. The iodine causes the formation
of stained complexes inside of the bacterial
cells. The bacteria are then carefully
rinsed with alcohol. The alcohol is
able to dissolve these complexes, but is
only to wash out the dye in bacteria
which have a thin cell wall (Gram negative).
Cells with a thick cell wall retain
the dye (Gram positive). Last, the cells
are counter-stained with a deep red safranin
dye to make the cells visible again,
which have lost the color in the washing
step.
Gram negative bacteria have a thin
cell wall between two membranes,
while Gram positive species have a
thick cell wall outside of a single cell
membrane. The Gram positive bacteria
represent a distinct line in the phylogenetic
tree of life, which was established
using genetic studies. The Gram staining
procedure therefore differentiates
the bacteria based on their phylogenetic
relatedness.
Personal experiences
During my work in the microbiological
laboratory, I have performed countless
Gram stains, with varying success.
I have discovered, that the reproducibility
of the procedure depends much on
the age of the culture. Some bacteria
behave differently depending on whether
the bacterial culture is still actively
growing or stationary. Gram positive
cells that are too old might appear as
being Gram negative. I even remember
one instance in which a pure culture of
a bacterial species had cells which
stained both Gram positive and Gram
negative. Evidently some of the cells in
the culture were already too old to retain
the stain, while others were still young
enough to stain as expected.
Sometimes the optics of the microscope
also complicated the matter.
Phase contrast optics generally made
the cells appear darker and occasionally
it was difficult to identify the true color
of the cells. In bright-field systems,
closing the condenser diaphragm too
much also introduces refractive patterns
around the cells, especially if the refractive
index of the bacteria is very different
from the surrounding medium. This
too made the staining reaction difficult
to see.
Impatience is also a problem. It is
not advisable to speed up the drying
process of the bacterial suspension by
heating the slide. This will cause the
cells to burst and they will stain Gram
negative because the blue–purple color
complex can then be washed out of the
cells.
Last, some bacterial strains are
Gram-indeterminate. This means that
they do not respond well to the staining
procedure and can not be distinguished
this way. With all of these uncertainties,
it is not surprising that molecular methods,
such as DNA analysis, have gained
so much popularity in recent years.
References
Gram, C. 1884. Über die isolierte Färbung der
Schizomyceten in Schnitt- und Trockenpraparaten.
Fortschritte der Medicin, Vol. 2, pages
185-189.
English translation of the article:
http://www.microbelibrary.org/images/stories/M
L_2.0/1884p215.pdf
■
Figure 2: The Phylogenetic Tree of Life. Genetic studies have shown that the Gram positive bacteria (circled) form a distinct
branch in the tree of life. The Gram staining procedure corresponds to the genetic results and is therefore useful for identification
purposes. Image: Public Domain by Eric Gaba (based on a NASA image)
MicrobeHunter Microscopy Magazine - October 2012 - 7

TESTING
Comparing objectives
Yes, there are some low-cost microscopes around, which do perform.
Oliver Kim
Here, right on my desk: A lowcost
educational microscope
(BMS 136 series) with four objectives
(4x, 10x, 40x, 100x oil). Monocular,
10x eyepiece. A single 0.5W
LED (corresponding to 20W halogen),
powered and with rechargeable batteries
(2x AA). Equipped with a 1.25 NA
condenser with an aperture diaphragm,
pre-centered. Mechanical stage. Mostly
metal construction. No Köhler illumination.
Price: just over EUR 200. Mass:
3544g. Variations of the microscope do
exist, such as the inclusion of a halogen
light instead of a LED, or binocular
versions.
The microscope was obtained for
evaluation purposes to check it it proves
1
to be useful for classroom use. The
ability for the microscope to be battery
operated was considered as being critical,
as electrical power supplies are not
available for every desk in the classroom
(the microscope had to be operated
outside of a lab, in regular
classrooms). All parts of the microscope
were "student-proof". It was therefore
not possible to remove the eyepieces
and condenser without special tools. It
was also not possible to detach the rotating
tube (which carries the eyepiece) of
the microscope. The only exception
were the objectives. These were of the
160mm DIN standard, could be unscrewed
easily and and could therefore
also be fitted on my more expensive
Olympus CH40 microscope. I wanted
to take advantage of this possibility and
compare the optics of the two instruments
by fitting the objectives of the
educational microscope on the Olympus.
The Olympus objectives were achromatic
bright-field objectives, the
objectives of the educational microscope
were of unknown correction (I
suppose also achromatic).
The CH40 was also equipped with a
digital camera and associated reduction
optics. I could therefore easily compare
the quality of the different optics. With
the exception of the objectives, everything
thus remained the same. The condenser
aperture diaphragm was set to
the value which corresponded to the
value printed on the objective. Both, the
Olympus objectives as well as the objectives
of the educational microscope
had the same numerical aperture (N.A.)
values. I have also made s few afocal
photographs through the eyepiece using
a separate compact camera in order to
obtain the full field of view (figures
4-6).
Despite the relatively low price of
the educational microscope, I was positively
surprised that the objectives produced
quite usable images. A quality
difference was visible for sure, but not
to the extent that I expected. The biggest
problem was a blurriness towards
the side of the field of view (figures
Figure 1: The Olympus CH40 microscope
(left) and a low-cost educational
microscope on the right. Both
microscopes use the 160mm DIN
standard and therefore allow for an
exchange of the objectives. The objectives
of the educational microscope
were mounted on the Olympus
and the quality of the optics could
thus be compared.
8 - MicrobeHunter Microscopy Magazine - October 2012

Comparing objectives
TESTING
4-6). This effect is more disturbing
when taking pictures, but not a big
problem when only working visually.
By operating the fine focus knob, one
could also bring these areas into focus.
Figure 6 shows a picture through the
eyepiece of the educational microscope
itself. There is much less blurriness.
Probably the smaller field of view that
the eyepiece produced eliminated the
critical areas at the side.
I also used the attached camera to
take pictures through the trinocular
head. This camera did not capture the
full field, but rather a rectangular section
from the center of the field of view.
Therefore the blurry sides were eliminated
from the picture. Some loss of
quality is still visible in the comparison
pictures, however (figures 2-3 and 6-9).
The 4x objective resulted in the worst
image quality at the sides, probably also
because of its wide field of view.
The short verdict
If you are looking for a low-cost
microscope, either for yourself or as a
present for your children, then I would
say that microscope that I tested can be
seen as a good reference on what to
expect from a EUR 200-250 microscope.
The microscope is definitely not
a toy and sufficiently solid to be taken
seriously. The image quality of the objectives
was generally comparable to
those of my CH40 microscope, at least
in the center of the field of view. People
who want to start with the hobby of
microscopy and who do not want to
invest too much money might consider
such a device. It is true that used microscopes
from more well-known manufacturers
(Zeiss, etc.) can also be
obtained in this price range. These microscopes
frequently can provide more
value for the money and even a greater
resale value. Used microscopes, however,
do pose a certain risk for those people
who do not know what to look out
for.
In recent years many large microscope
manufacturers have moved away
from the 160mm DIN standard (finite
optics) for the objectives, in favor of the
more modern infinity systems. One of
the nice things about the traditional 160
mm system is the ability to exchange
the objectives between the microscopes.
In contrast to infinity optics, the traditional
DIN standard is manufacturer
independent and there are plenty of
cheaper second hand objectives available,
should one or the other of them
break (which is a possibility in educational
settings).
When buying low-cost microscopes
the presence of standardized optics is
probably one important indicator on
whether the microscope fulfills minimum
quality considerations. Many toy
microscopes do not have standardized
optics and may therefore be distin-
Figures 2 and 3: 4x objective comparison.
The left image is from the Olympus,
the right image from the
educational microscope. While the
overall image quality is similar, the
objectives of the educational microscope
does show some blurring at
the corners.
2 3
MicrobeHunter Microscopy Magazine - October 2012 - 9

TESTING
Comparing objectives
4 5
6
Figures 4 and 5: Afocal photograph through the 4x objective
(left Olympus objective, right educational microscope objective).
The images shows the fluff of a thistle plant. The objective
of the educational microscope does show a
significant blurriness towards the sides, which only becomes
strongly evident when using a wide-field eyepeice.
Figure 6: Afocal photograph through the 4x objective and
the native eyepiece of the microscope. The eyepiece produced
a lower field of view and therefore eliminated some of
the blurry areas at the sides. The black line is a pointer.
Figures 7 and 8: Comparison of the 10x objective (left Olympus
objective, right BMS 136 objective). The image shows
the cross section of a pine flower.
Figures 9 and 10: Comparison of the 40x objective (left
Olympus objective, right BMS 136 objective). Pine flower.
The circular ring-shaped structures appear to be the vascular
tissue. The objectives compared quite well.
guished from the better microscopes
this way.
The harsh reality is, that microscopes
which are used for educating
students are exposed to significant
stress. Students do make mistakes, this
is part of the learning process, and unfortunately
some of the mistakes may
result in damaged equipment. Despite
warnings and instructions, I have encountered
students who use non-oil immersion
objectives with immersion oil.
The front lenses of objectives were
cracked because they were crashed into
the specimen slide. I also remember one
objective, which had a spring-loaded
front. The whole spring-loaded front
part was pushed in and was stuck. There
was mounting medium all over the objective,
causing the spring-loaded front
to be glued in place. Evidently the student
who used this microscope was not
patient enough to wait for the mounting
medium to dry and rotated the objective
right into it.
With these realities in mind, I think
that it is better to use very cheap objectives
for educational use. Dust and dirt
will soon reduce the image quality anyway.
Higher quality objectives might
not show the optical aberrations of lower
cost objectives, but I seriously doubt
if this is worth the extra cost considering
the other factors that reduce image
quality. And let’s be honest about it: I
doubt that the students even notice the
blurriness at the sides of the field of
view.
■
10 - MicrobeHunter Microscopy Magazine - October 2012

Comparing objectives
TESTING
7 8
9 10
MicrobeHunter Microscopy Magazine - October 2012 - 11

OBSERVATIONS
Plant Leaves
Observing Plant Leaves
Clear nail polish can be used to make impressions of plant leaves.
The leaves are the photosynthetic
organs of a plant. The cells are
packed with chloroplasts, which
convert CO 2 gas from the atmosphere
and water to glucose, using the energy
of sunlight. The produced glucose is
then either respired and used as an energy
source, or it is converted to other
organic substances needed for plant
growth. The cells of a leaf also produce
molecular oxygen (O 2 gas) as a waste
product. This gas is either given off into
the atmosphere, or stored inside the leaf
for the night, to be used for cell respiration.
The Stomata
In order to provide the cells of the
leaf with sufficient CO 2 and to allow for
the escape of O 2, the bottom side of the
leaves contain countless openings, the
stomata. Each stoma can be opened and
closed by the expanding and contracting
action of two guard cells. The stomata
open during the day to allow for the free
movement of gases into and out of the
leaf. At night, when photosynthesis
does not take place, the guard cells
close the stomata to minimize the loss
of water. Exceptions do exist, such as
the CAM (Crassulacean acid metabolism)
plants, which grow in hot and dry
environments. These plants close the
stomata during the day to further reduce
the water loss. These plants then open
the stomata at night to allow CO 2 to
enter the leaves. The CO 2 is fixed and
the product is stored in vacuoles to be
used for photosynthesis during day.
The stomata and associated guard
cells can be made visible in several
ways. Thin leaves can be placed directly
Oliver Kim
on the slide for observations. The light
intensity must be sufficiently high to
pass through the leaf. The distinctive
shape of the stomata and guard cells can
then be seen, but the quality of the image
is naturally not high. Carefully microtoming
the leaf would be another
possibility, but this can become a problem,
especially when leaf observation is
to be done with students or children,
when safety issues start to play a role.
Making leaf impressions is probably
one of the least complicated and easiest
methods to make the surface texture of
the leaves visible.
Figure 1: Leaf impressions of the
lower epidermis. Many stomata are
visible (the oval structures).
1
12 - MicrobeHunter Microscopy Magazine - October 2012

Plant Leaves
OBSERVATIONS
2
Figure 2: Some clear nail polish is
applied to the bottom side of a leaf
and allowed to dry over night. I applied
the nail polish several times
over each other, in order to make the
film of thicker and more stable. Painting
over the leaf veins makes removal
difficult, however.
Figure 3: The dried nail polish is
carefully removed by first lifting the
corner with a knife and then peeling it
off using your fingers.
Figure 4: The nail polish in oblique
illumination. Stomata are clearly visible.
3 4
Making leaf impressions
Some glue or clear nail polish is
applied to the bottom side of a leaf and
allowed to dry completely. One should
not apply the glue over the leaf veins, as
this makes it more difficult for the glue
to be separated after drying. The film is
allowed to dry completely (one day)
and then carefully peeled off and
mounted on a slide for microscopic investigation.
It may be necessary to use
a sharp object to start peeling away the
nail polish, the rest of the dried nail
polish should come off quite easily as
the waxy cuticle on the surface of the
leaves prevents the nail polish adhering
to the cells. it goes without saying, that
the solvent in the nail polish harms the
leaves so that it is advisable to use the
fallen leaves from a tree. Alternatively
one can use water-based white wood
glue, which should be less problematic
in this respect. I found out that the white
wood glue is more flexible than the nail
polish and may deform more during the
peeling process.
The thin film of nail polish is then
carefully pressed against the glass slide
to reduce warping. It is then observed
microscopically in the form of a dry
mount.
Making leaf impressions, while
much easier than trying to cut the leaf
into thin sections, does have the disadvantage
that individual cell organelles,
such as the green chloroplasts in the
guard cells, naturally are not visible.
Leaf impressions that are obtained
this way are, naturally, low in contrast
and require you to close the condenser
aperture diaphragm. The leaf-impressions
are, however, very suitable for
observation in oblique illumination.
This technique allows light to strike the
specimen (i.e. the piece of glue carrying
the leaf impression) only from one side,
resulting in a characteristic 3-dimensional
appearance (figure 4).
The next obvious step would be the
making of a permanent mount of the
nail polish impressions. This is likely to
be difficult, as the organic solvent of
mounting media is likely to soften or
MicrobeHunter Microscopy Magazine - October 2012 - 13

OBSERVATIONS
Plant Leaves
5
14 - MicrobeHunter Microscopy Magazine - October 2012

Plant Leaves
OBSERVATIONS
even dissolve the impression. It is also
important that the refractive index of the
mounting medium is different from the
refractive index of the nail polish impression,
otherwise the structures will
not be visible. Evidently there are still
many opportunities for experimentation.
Other leaf tissues
6
UE
A typical deciduous plant leaf is
composed of several layers. The top
most layer of a leaf is a cell-free layer of
wax, the cuticle. Its function is to reduce
the loss of water from the cells. The
waxy cuticle is produced by the upper
epidermis. This layer of cells does not
contain chloroplasts in order to allow
sunlight to pass through unhindered.
The palisade mesophyll is a layer of
packed cells beneath the upper epidermis.
The cells are arranged vertically
and contain many chloroplasts. Their
vertical arrangement and high density
makes them an efficient layer for photosynthesis.
Spaces between the individual
palisade cells allow for the diffusion
of CO 2 gas. Beneath the palisade mesophyll,
one can find the spongy mesophyll.
It is a loosely packed layer of
cells, containing (as the name "spongy"
suggests) many air spaces. This is the
place where the gases CO 2 and O 2 are
stored. Many cells are in contact with
the air spaces and therefore the total
surface area to loose water is also quite
high. The lower epidermis is a single
layer of cells on the bottom part of the
leaf. It is the plant tissue which contains
the guard cells and the stomata. With
the exception of the guard cells, the
lower epidermis is free of chloroplasts
(figure 6).
■
Figure 5 (opposite page): This image
shows a stack of the nail polish impression
of the leaf surface.
Figure 6: Cross section through a
leaf. Abbreviations: UE: upper epidermis;
P: palisade mesohyll, S: spongy
mesophyll, LE: lower epidermis.
Figures 7 and 8 (next page): The epidermis
of a tulip leaf.
LE
S
P
MicrobeHunter Microscopy Magazine - October 2012 - 15

OBSERVATIONS
Plant Leaves
7
8
16 - MicrobeHunter Microscopy Magazine - October 2012

Desmids
REFERENCE PLATE
Staurodesmus tumidus
Mike Guwak
Full name: Staurodesmus tumidus
(Brébisson ex Ralfs)
Teiling 1967: 578
Shape: The cells are large and
wider than they are long. The
semicells can be elliptical or
strongly rounded in a hexagonal
arrangement. The septum is
rounded in the center and strongly
widened towards the sides. The
cell wall contains scattered pores.
According to Meindl (1987), the
desmid may belong to the genus
Pleurenterium, based on the position
of the chloroplasts and other
cell organelles in the cell.
Size: 110-130mm
Occurrence: This is a freshwater
species.
MicrobeHunter Microscopy Magazine - October 2012 - 17

REFERENCE PLATE
Desmids
References
"Species Detail :: Algaebase." Algaebase :: Listing the World's Algae. N.p., n.d. Web. 31 Oct. 2012.
http://www.algaebase.org/search/species/detail/?species_id=35537
Lenzenweger, R. (1997). Desmidiaceenflora von Österreich Teil 2. Bibliotheca Phycologica 102: 1-216, 44 pls.
Image Credit
Image copyright Mike Guwak (2012).
http://www.mikroskopie-main-taunus.de
mike.guwak@mikroskopie-main-taunus.de
18 - MicrobeHunter Microscopy Magazine - October 2012

Rotifers
GALLERY
Rotifers found in the bottom of my aquarium,
possibly Ptygura sp. Camera: Optikam B1
by Luca Monzo.
Send images to editor@microbehunter.com - MicrobeHunter Microscopy Magazine - October - March 2012 - 19

GALLERY
Annelid:
Pictures of Aeolosoma sp.
Camera: Optikam B1 at 1,3 MP and
10xachromatic objective
By Luca Monzo
20 - MicrobeHunter Microscopy Magazine - March October 2012 - Send images to editor@microbehunter.com

Annelid:
GALLERY
Send images to editor@microbehunter.com - MicrobeHunter Microscopy Magazine - October - March 2012 - 21

GALLERY
Water life
These pictures show of microalgae and
cyanobacteria found near the lights of
my aquarium.
Bottom right: water flea
(Chydorus sp.)
Single images were taken with a
microscope camera Optikam B1 at full
resolution (1280 x 1024 pixels)
22 - MicrobeHunter Microscopy Magazine - March October 2012 - Send images to editor@microbehunter.com

Amoeba
GALLERY
Two specimens of what I think is Thecamoeba,
an amoeba that appears to
possess a voracious appetite.
Objective: 20x; illumination: DIC; exposure:
1/13s (top image) and 1/25 s (bottom
image), at 200 ISO.
By R. Nassar
Thanks goes to all contributors for giving
their permission to republish their images.
Send images to editor@microbehunter.com - MicrobeHunter Microscopy Magazine - October - March 2012 - 23

What’s this? Answer on page 3.
24 - MicrobeHunter Microscopy Magazine - October 2012