[en] The small group of hydrogen-deficient carbon-rich variables known as R Coronae Borealis (RCB) stars contains about 40 stars, some of which have been classified RCB on rather flimsy evidence. Earlier notes in this series have shown V₅₀₄ Cen, previously classified RCB:, to be a cataclysmic variable and AE Cir, classified RCB, to be a symbiotic star. In the present paper, spectroscopy of V618 Sgr and MT Pup is reported; the former appears to be a symbiotic star, the latter a cataclysmic variable. (author)