  RX J1914.4+2456 and RX J0806.3+1527 have been proposed as double degenerate
binaries with orbital periods of 569s and 321s respectively. An alternative
model, in which the periods are related to the spin of a magnetic white dwarf
in an intermediate polar system, has been rejected by other authors. We show
that a face-on, stream-fed intermediate polar model for the two systems is
viable and preferable to the other models. In each case, the X-ray modulation
periods then represent the rotation of the white dwarf in the binary reference
frame. The model explains the fully modulated X-ray pulse profiles, the X-ray
spectra, the antiphase between X-ray and optical/infrared modulation, the lack
of longer period modulation, and the low level of polarization. The optical
spectrum of RX J0806.3+1527 suggests that Balmer series lines are present,
blended with HeII lines. This is unlike the spectra of any of the known AM CVn
stars and suggests that the system is not a double degenerate binary. The
optical spectrum of RX J1914.4+2456 has spectral features that are consistent
with those of a K star, ruling out the double degenerate models in this case.
The lack of optical/infrared emission lines in RX J1914.4+2456 may be
attributed to a high mass accretion rate and its face-on orientation. Its
reported period decrease may be a short term spin-up episode driven by the
current high M-dot. Finally we suggest that there is an observational selection
effect such that the face-on intermediate polars that are detected will all
have a stream-fed component, and the purely stream-fed intermediate polars that
are detected will all be face-on systems.
