ON THE ORBITAL PERIOD OF THE NEW CATACLYSMIC VARIABLE EUVE J2115-586

We have obtained phase-resolved spectroscopy (3660-6040 Angstrom) of t he recently discovered cataclysmic variable EUVE J2115-586 using the 7 4-inch telescope at Mount Stromlo Observatory. The radial velocity is modulated over a period of 110.8 min with a possible cone-cycle-per-da y alias of 102.8 min, and a semiamplitude of approximate to 270 km s(- 1) at H beta and approximate to 390 km s(-1) at He II lambda 4686. The spectroscopic appearance (H I Balmer, Ca II, He I, He Il emission lin es), the orbital period, and the velocity amplitude indicate that this cataclysmic variable is probably an AM Her type; the absence of cyclo tron humps indicates a low intensity magnetic field (B<20 MG). Extreme ultraviolet emission phased at the orbital period shows evidence of v ariability, but additional EUV/soft x-ray observations are recommended . (C) 1996 American Astronomical Society.