Hello again,

the pretty guy pictured here is a nauplius.

Nauplius is the larva stadium of a small aquatic cancer. This fellow is
quite big; its size is about 1/50 of an inch.

The red stain in the middle of the organism's front part may be familiar
to you if you have been watching my euglena acus posting. It is the eye,
though a more complex one as euglena acus has it. A protozoologist might
say this is not a "real" protozoon for it consists of more than one
cell. Right, but microscopers usually don't care about that as long as
the damn beast looks good in the microscope; this one certainly does.

The brown bubbles are the digestion/excretion organs; I am not sure if
one of them probably is the heart.

By the way, if you compare the picture I posted yesterday (Paramecium
caudatum) to this one you may have noticed that the appearance of the
images is different. This is because there were different methods of
illumination being used: Today's posting uses "brightfield" illumination
using the light that passes directly from the light source through the
object. Yesterday's image used "phase contrast" illumination which is,
in brief, based on the interference of two light rays coming from the
same light source. The interference produces the halos around the
object's edges and makes structures of different refraction indices,
that is different optical density, clearly visible without dyeing or
even harming the object. I usually favor photographing protozoa alive
without artificially adding colours or chemicals; in this case, I often
experiment with illumination to enhance contrast. Phase contrast is
great for that; I'll show you some other techniques later.

Don't know much more to say about nauplius, so just enjoy the picture.

Bye for today,

Ralf


Content-Type: image/jpeg; name="Nauplius.jpg"



Comments
========
Date: 18 May 1998 02:17:55 -0000
From: nobody@nsm.htp.org
Remailed-By: Anonymous Remailer
Subject: Re: Protozoa - nauplius

On Sun, 17 May 1998 21:17:03 +0200 Schmode wrote:

>Nauplius is the larva stadium of a small aquatic cancer.

The German word "Krebs" means both a disease and a crustacean.
But in English, cancer is only the disease, and the word for the
crustacean is "crab". Presumably the latter is intended. i.e.

"Nauplius is the larval stage of a small aquatic crab."

But keep it up; I'm collecting all the ones you've posted, expecially
with the excellent descriptions. I only posted because non-German
speakers might not figure this one out.


Comments
========
From: emilmanc@tin.it
File To Comment: animal1/Nauplius-Protozoan.jpg

I don't know why you put this animal between the PROTOZOA
You have to put it in ARTROPHODA or CRUSTACEA
bye

emiliano