Watch the Stinger online guitar lesson by TrueFire from Play Acoustic Guitar 6: Lick Lexicon
Stinger - Lick #28 is a video guitar lesson presented by Joe Dalton and is sourced from 50 Acoustic Blues Licks You MUST Know.
This blues lick has a ragtime flavor to it. Notice how the ascending pick up notes are complemented by the descending 6th chords and how they act as the answer to the ascending melody. I think the use of chromatics brings out the ragtime feel. Start out slowly with this one. The speed and the smoothness will come with a little bit of practice.