Why am I am getting an extra line in GridView with the following text in the
1st column:  "System.Web.UI.WebControls.TableRow"

Here's partial listing of my code:
..................
           grid.DataSource = loadTable(ds);
           grid.DataBind();
.................
   private DataTable loadTable(DataSet ds)
   {
       DataTable dt = new DataTable();
       DataTable myDataTable = ds.Tables[1];
       int cols = myDataTable.Columns.Count;

       TableHeaderRow thr = new TableHeaderRow();
       for(int i = 0; i < cols; i++)
       {
           TableHeaderCell thc = new TableHeaderCell();
           thc.Text = myDataTable.Columns[i].ColumnName;
           thr.Cells.Add(thc);

           DataColumn dcol = new DataColumn(thc.Text,
typeof(System.String));
           dt.Columns.Add(dcol);
       }
       dt.Rows.Add(thr);
       return dt;
   }