• Rat 

        Contributor:Colorado Agricultural College
        Date:undated
        A skinny mouse stands on a black backdrop. "B2343" and "4323" with a male symbol are drawn on the bottom of the picture.
      • Rat 

        Contributor:Colorado Agricultural College
        Date:undated
        A heavier mouse stands on a black backdrop. "B2344" and "4383" with a male symbol are drawn on the bottom of the picture.