The General Proctologist, a variation of Drury's "General Practitioner", was tied by contributing tyer, Scott Howell of Bothell, WA. See his notes below.
SCOTT'S NOTES: This fly, originated by Colonel Esmund Drury, is a must-have for Salmon and Steelhead. Sea-run Cutthroat Trout can also be landed using G.P.'s tied on smaller hooks (#7 and #6). This versatile pattern is also dressed in Black, Purple, Pink, Red, Claret, and Chartreuse. I've also used (successfully) combinations of Black and Blue on overcast days ( see General Proctologist, Blue ).
With no disrespect intended (especially to Col. Drury!), I renamed this fly because alligning and tying in the Carapace can be (for me) a genuine pain in the 'back side'!