This company had operated an electric interurban railway between Dayton and Xenia, a distance of 16 miles, since January, 1900. They early on operated a city streetcar service over the inner portion of this route, to the east side Belmont area.

After 1937 only the city line segment was kept as a rail streetcar line. (The carbarn was some 4 miles beyond the Belmont loop.) D-X drastically cut their operating costs by converting the Belmont line to ETB on October 1, 1940. At that time, D-X looped in the Dayton CBD, not being through routed.

They operated 12 dark-green Pullman-Standard coaches, trimmed in cream. In 1947 they purchased one additional Pullman, which sometime later they loaned to the Oakwood system for a year or so.

Many of the D-X executives also served as officers of the larger City Railway Company. Be that as it may, the D-X merged with City Railway Company on November 1, 1955. The merger resulted in the City Transit Company. Now only Oakwood remained separate, but not for long.