Here's the sign that marks the Lyell Canyon trailhead, in the parking lot of the Tuolumne Meadows Lodge. Unless, that is, the park's Keepers Of The Signs have found this page and decided to change the sign just to keep hikers on their toes. Park employees are well known for their fabulous senses of humor.
Except for Donohue Pass, all the destinations on the sign require you to fork off the Lyell Canyon trail a little over a mile in and detour to the southwest. "H.S.C.", by the way, usually means "High Sierra Camp" when you're in Yosemite.