Image No.1 (Horizontal field of view 0.22mm)
Image of a small portion of a posterior lateral spinneret showing silk spigots. A total of 4 of the spigots visible are emitting a single strand of silk. Follow each strand back to its source spigot to see each of them. This image is a 50% crop of the original frame.
Reflected diffused fiber-optic illumination.
136 images at .5 micron increments, Nikon 40xW Achromat
Image No.2 (Horizontal field of view 0.22mm)
Same region of that seen in Image 1 but a single image focused on the tip of the emitting spigot center left. Two other silk strand are visible in portion to the center and right. This image is also a 50% crop of the original frame.
Reflected fiber-optic illumination.
1 single image, Nikon 40xW Achromat
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Image No.3 (Horizontal field of view 0.34mm)
Deep stack of a small portion of a posterior lateral spinneret showing a “field” of silk spigots. Un-cropped image. Although difficult to see, there are two spigots with silk strands still attached amongst the multitude. The image comes nowhere near what a SEM shows but it is fun to make some comparisons.
Reflected diffused fiber-optic illumination.
392 images at .5 micron increments, Nikon 40xW Achromat
Image No.4 (Horizontal field of view 0.34mm)
A shorter stack of a small portion of a posterior lateral spinneret showing a single spigot clearly releasing a silk strand. An additional silk strand appears to be lying on the spinneret surface unattached to any spigot. Un-cropped image.
Reflected diffused fiber-optic plus EPI illumination.
50 images at .5 micron increments, Nikon 40xW Achromat
Leitz Ortholux microscope
4X Leitz projection eyepiece plus 1/3x relay lens
Canon 50D
Zerene PMax and/or DMap stacking.
Processing in Photoshop and Bibble Pro 5.
Thanks for looking at my final set of images in this spinneret series. My goal has been achieved. Although it was the original goal of this study (see Part 1 and 2), I never found silk during that phase. I was unaware that any silk was present until the higher magnification and resolution of the 40x objective provided fleeting glimpses of silk as seen in Image #2. I was very taken by the similarity that I was seeing, as I focused in and out, to SEM images showing silk strands still attached. Unfortunately the stacking software cannot produce an image like a SEM but the evidence is there. Look up the SEM work of Dennis Kunkel to see how much more amazing a SEM image can be.
I have roughly measured the silk strand leaving the spigot at approximately 2.5 microns. How many individual spigots would be producing silk as this orb web weaving spider creates the “strand”, that we actually see with our naked eye, could number a thousand or more.
Mitch, now you can see that when strand production is in full swing on a living subject many hundreds of these individual strands are what is needed to create the result we see with the naked eye. And it is my understanding that different glands produce different kinds of silk based on the application. Amazing!!!
Walt
