From the pattern:
These mittens are worked in the round with two-color fair-isle. The hand motif is inspired by graceful meandering vines (or blazing fire tongues, depending on your interpretation and choice of color), and the palm motif is the falling spring leaves (or fiery sparks).
These mittens fit like a glove: snug on the cuffs and roomy on the palm so you won’t have any trouble stretching that thumb! The fit is incorporated in the invisible increases (hidden as vines branching out).

• Pattern is written for mirroring left and right mittens.
• Bobbles can be replaced by the leaf motifs (as on palm side).
• Invisible increases are worked using the raised increase method, also known as Cat Bordhi’s LLinc (Left-Leaning increase). All increases in this pattern are left-leaning.
• Twisted stitches are basically cables worked over 2 sts, which are done without using cable needles.