Tractate Demai
Mishnah Demai, the third tractate of Seder Zeraim, deals with produce bought from a seller who cannot be fully trusted on tithing. Like almost every tractate in this order, its 7 chapters and 53 mishnayot were never given a Gemara in Babylon.
Demai - Chapter 1 Produce exempt from demai status and produce that remains subject to it despite its doubtful origin.
Demai - Chapter 2 Using demai produce for purposes other than eating, and the levels of trust granted to a seller.
Demai - Chapter 3 Rules for buying and selling demai produce, especially from someone not careful about tithing.
Demai - Chapter 4 Feeding demai to a guest or an animal, and business transactions involving it.
Demai - Chapter 5 Cases where demai is mixed with other produce, and the effect on its status.
Demai - Chapter 6 Arrangements between partners when one is careful about tithes and the other is not.
Demai - Chapter 7 Additional cases of partnership and shared meals involving demai.
Talmud Bavli