  The comparison of optical and 2MASS near-infrared photometry for large
samples of catalogued proper motion stars has the potential to discover
previously unrecognized nearby objects of rare type. In this paper we present
the discovery of two new carbon dwarfs, LSR 2105+2514 and LP 758-43, which were
drawn from proper motion lists and which lie in a sparsely populated part of
optical/near-IR color-color space. Their optical spectra, exhibiting
absorptions by C_2 and/or CN, are discussed. LSR 2105+2514 is believed to lie
within 200 pc and would have M_(K_s) < 6.7, making it lower in luminosity than
any carbon dwarf with a measured trigonometric parallax. LP 758-43, which is
not as red but still probably cooler than the best studied carbon dwarfs, is
believed to lie within 360 pc. Using our optical/near-infrared selection
technique on published lists of proper motion stars, we hope in the near future
to expand further the current sample of carbon dwarfs, which numbers only 31
objects at this writing.
