1. IN CLUTCH APPARATUS FOR PLANTERS AND THE LIKE, A SUPPORTING FRAME, A DRIVE SHAFT MOUNTED FOR CONSTANT ROTATION ON THE FRAME AND HAVING A DRIVING SPROCKET SECURED THERETO, A HOUSING MOUNTED ON AND JOURNALING THE DRIVE SHAFT, AN INTERMITTENLY DRIVEN SPROCKET TO THE HOUSING COAXIALLY WITH SAID SHAFT AND ROTATABLE WITH THE HOUSING, AN IDLER SPROCKET MOUNTED FOR FREE ROTATION ON THE HOUSING, AN ENDLESS CHAIN OPERATIVELY CONNECTING SAID DRIVE SPROCKET AND SAID IDLER SPROCKET, AND LOCKING MEANS MOUNTED IN SAID HOUSING AND OPTIONALLY ENGAGEABLE WITH SAID ENDLESS CHAIN FOR LOCKING THE LATTER AND THE HOUSING TOGETHER AS A UNIT TO CAUSE THE HOUSING AND THE INTERMITTINGLY DRIVEN SPROCKET TO REVOLVE ABOUT THE AXIS OF SAID DRIVE SHAFT.