  We have obtained long-slit far-ultraviolet (1150--1730 A) spectra of the R
Coronae Borealis (RCB) stars V854 Cen and RY Sgr, near maximum light and
pulsational phase zero, with the Space Telescope Imaging Spectrograph (STIS) on
Hubble Space Telescope (HST). The far-UV spectrum of each star shows a
photospheric continuum rising steeply toward longer wavelengths, and a
prominent emission feature at C II 1335. RY Sgr displays a second, but fainter,
emission attributed to Cl I 1351 (which is radiatively fluoresced by C II
1335), but Cl I is weak or absent in V854 Cen. Most surprisingly, the C II
emission of V854 Cen is significantly extended along the slit by +/- 2.5
arcsec, about 6 x 10^3 AU at the distance of the star. The C II feature of RY
Sgr exhibits no such gross extension. Nevertheless, subtle broadenings of the C
II emissions beyond the point response profile suggests inner clouds of radius
\~0.1 arcsec (250 AU) around both stars. V854 Cen is only the third RCB star
after R CrB and UW Cen known to have a resolved shell.
