The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.
The green blob contained in this case is a pupa in the early stages of transformation from larva to the final stage we generally picture and imitate. This specimen and several like it were fixed to a rock I picked up, and each one had the front of its case sealed off, protecting the helpless pupa from predation. It's neat to see the insect part-way through such a radical transformation.
It was very hard to extract this thing from its case, so there's a bit of extra goo near the head from where I accidentally punctured it.
This caddisfly was collected from Cayuta Creek in New York on April 14th, 2007 and added to Troutnut.com by Troutnut on April 22nd, 2007.