  We define an enhanced spectral classification scheme for M dwarf stars, and
use it to derive spectral classification of 104 northern stars with proper
motions larger than 0.5"/yr which we discovered in a survey of high proper
motion stars at low galactic latitudes. The final tally is as follows: 54 M
dwarfs, 25 sdK and sdM subdwarfs, 14 esdK and esdM extreme subdwarfs, and 11 DA
and DC white dwarfs. Among the most interesting cases, we find one star to be
the coolest subdwarf ever reported (LSR2036+5059, with spectral type sdM7.5), a
new M9.0 dwarf only about 6pc distant (LSR1835+3259), and a new M6.5 dwarf only
7pc from the Sun (LSR2124+4003). Spectroscopic distances suggests that 27 of
the M dwarfs, 3 of the white dwarfs, and one of the subdwarfs (LSR2036+5059)
are within 25pc of the Sun, making them excellent candidates for inclusion in
the solar neighborhood census. Estimated sky-projected velocities suggest that
most of our subdwarfs and extreme subdwarfs have halo kinematics. We find that
several white dwarfs and non metal-poor M dwarfs also have kinematics
consistent with the halo, and we briefly discuss their possible origin.
