As much as he has deserved. When a person employs another to do work for him, without any agreement as to his compensation, the law implies a promise from, the employer to the workman that he will pay him for his services, as much as be may deserve or merit. In such case the plaintiff may suggest in his declaration that the defendant promised to pay him as much as he reasonably deserved, and then aver that his trouble was worth sucli a sum of money, which the defendant has omitted to pay. This is called an assumpsit on a quantum meruit.
When there is an express contract for a stipulated amount and mode of compensation for services, the plaintiff cannot abandon the contract and resort to an action for a quantum meruit on an implied assumpsit.