Viroca Jātaka (No.143)
The Bodhisatta was once a lion and lived in Kañcanaguhā. He granted to a jackal the favour of being allowed to inform him of the presence of prey, the animal being given a portion of the carcase in return for this service. In time the jackal grew strong and begged to be allowed to kill an elephant. The lion reluctantly agreed to this, but the jackal, in his attempts to leap on to the elephant, missed his aim and fell to the ground where he was crushed to death.
The story was related in reference to Devadatta’s attempt to pose as the Buddha and his failure to do so, wherefore he received a kick on the chest from Kokālika (q.v.) The jackal is identified with Devadatta. J.i.490‑3.