Fall Webworm Silk
This is an image of the silk from Hyphantria cunea, the Fall
Web Worm. The
caterpillars of this moth form tents in the branches of trees in the autumn of the year.
The silk
forming the tent of Hyphantia cunea varies wildly in diameter. As the caterpillar grows
it forms a
thicker silk.
Transmitted Oblique Illumination
Definition/Function:
Hyphantia cunea is a nearly all white moth that is wide spread in North America, Asia, and
Europe. Transmitted oblique illumination enhances contrast, retains resolution, and has
greater depth of field. It also indicates the relative refractive index of the particles by
the side that is shaded. The silk has a higher refractive index than the mounting medium so
all the fibers are shaded on the left side. A downside of oblique illumination is that
contrast and resolution are orientation dependent. The closer the fiber is to being parallel
to the beam the fainter the fiber. A curved fiber may disappear and then reappear as it
curves.
Significance in the Environment:
Characteristic Features:
Associated Particles:
References:
