The defendant made a special contract with the plaintiffs as copartners to do work for him. In any suit to enforce this contract or any liability growing out of it, both partners must be joined as plaintiffs. The defendant contracted with them jointly, not with either of them separately. The dissolution of the partnership before the work was completed had no effect upon the rights or liability of the defendant. It did not authorize the plaintiffs to sever the contract and sue the defendant separately. They must still sue jointly. Page v. Wolcott, 15 Gray, 536. Having fully performed the contract on their part, so that nothing remains but a mere duty of the defendant to pay money, they may maintain either of the common counts which is appropriate. Morse v. Sherman, 106 Mass. 430. Exceptions overruled.