What Race am I? Ethnicity?

Oddly, the US census definitions of “white” and “Asian” do not include Caucasian (e.g. Chechen) and central Asian (e.g. Kazakh) people:

http://www.census.gov/prod/cen2010/briefs/c2010br-05.pdf

http://www.census.gov/prod/cen2010/briefs/c2010br-11.pdf

Is there an option for “other”, writing in “Russian, Chechen, Kazakh, and unknown”?