We present a CFH12K wide field survey of the carbon star population in and around NGC 3109 .
Carbon stars , the brightest members of the intermediate-age population , were found nearly exclusively in and near the disk of NGC 3109 , ruling out the existence of an extensive intermediate-age halo like the one found in NGC 6822 .
Over 400 carbon stars identified have \langle M _ { I } \rangle = -4.71 , confirming the nearly universality of mean magnitude of C star populations in Local Group galaxies .
Star counts over the field reveal that NGC 3109 is a truncated disk shaped galaxy without an extensive stellar halo .
The minor axis star counts reach the foreground density between 4 ^ { \prime } and 5 ^ { \prime } , a distance that can be explained by an inclined disk rather than a spheroidal halo .
We calculate a global C/M ratio of 1.75 \pm 0.20 , a value expected for such a metal poor galaxy .