Image 1
End of leg four showing the calamistrum on the metatarsus segment of the leg. The spiders abdomen is in the background.
Leitz UO 6.5X Achromat
Diffused fiber optic illumination.
26 images at .001 inch increments.
Image 2
Detail of the metatarsus leg segment and the calamistrum comb.
Nikon 20X Achromat
Diffused fiber optic illumination.
254 images at 1 micron increments.
Image 3
High magnification attempt at revealing the location of the opening in the hair that exposes the fine cuticular teeth. These comb the silk from the cribellum. The opened slit is visible where the hair is bent or curved. The cuticular teeth are beyond the resolution of my optical microscope.
Leitz UO 75X Apo., Oil, Plus mirror condenser. Full EPI illumination.
47 images at 1/2 micron increments
Image 4
High magnification shot of the last 3-4 hairs of the calamistrum at the tarsal end. The difference in the calamistrum hairs verses the three normal leg hairs is apparent.
Leitz UO 75X Apo., Oil, Plus mirror condenser. Full EPI illumination.
89 images at 1/2 micron increments
Leitz Ortholux microscope
4X Leitz projection eyepiece plus 1/3x relay lens
Canon 50D
Zerene PMax stacking.
Processing in Photoshop, Bibble Pro5
Spiders of the crebulate type have a silk producing organ called the cribellum. It produces tens of thousands of minute silk strands only 0.01 micrometers in diameter.
A comb like feature is found on the rear legs. However the hairs are far from the most interesting feature of the calamistrum. On the surface of the hairs, similar to seeing the corn seeds exposed when first stripping an ear of corn, is a row of micro fine teeth. These are the objects that actually comb the strands of silk, only 0.01 micrometers in diameter, into a wooly like strand.
Our subject is the same spider of genus Ubolorus that is in Spiders No. 40.
Walt
