Abstract
Two new rumen ciliates, Polymorphella bovis sp.n. and Entodinium longinucleatum forma spinolobum f.n., from the zebu cattle in Thailand were described. P. bovis is flask-like in shape, with two ciliary zones: the larger zone in the anterior one-third area and the smaller zone in the posterior extremity of body. E. longinucleatum f. spinolobum has a very long macronucleus, and two spines and one lobe at the posterior extremity of body. At that time, the problem on the description of so-called E. longinucleatum group was discussed.
