Blackstone B.H. Nymph

Note 1: 
This fly is heavily weighted and is to be fished very slow along the
bottom.

Note 2: 
It takes years for the Giant Stonefly to mature, therefore there are large
nymphs all season in the streams they inhabit.  Fishing a large dark (black)
stonefly nymph can be productive almost anytime, in particular the late spring
when many are on the move to hatch.