Sent from Knights Manor Way, Dartford DA1 5SJ

Postmark

Circular date stamp (cds) and partly readable.
 
Caddis Fly Larva
 
The caddisflies are small moth-like insects having two pairs of hairy membranous wings. They are closely related to moths and butterflies. Caddisflies have aquatic larvae and are found in a wide variety of habitats such as streams, rivers, lakes, ponds, spring seeps, and temporary waters. The larvae of many species make protective cases of silk decorated with gravel, sand, twigs or other debris; others live without a case.  Caddisfly larvae excrete silk from salivary glands near their mouths, for case building. The cases are open at both ends, with the larva drawing oxygenated water through the back of the case, over the gills. The front of the case is usually wider and it is to this end that they add material as they grow. Their abdomens are soft but their tougher front ends project from their larval tubes allowing them to walk, dragging their cases along with them.

Designer: Kate Stephens
Illustrator: Chris Wormell
Printer: Walsall Security Printers (with two phosphor bars).