Populate Listbox With Column Headers From Multiple Sheets

I am trying to go through each worksheet and if the worksheet name is Hematology then the header columns will be put into the listbox (ListBox1). The first row of the header is the parameter and the second is the units. Ideally I'd like column 1 to have the first headr row and column 2 to have the second header row. Once the listbox is completed, the user can select multiple columns by the header and those columns will be deleted. I have the ListStyle set to 1-fmListStyleOption and MultiSelect set to 1-fmMultiSelectMulti

The only thing I get when I run the rubroutine is a userform (Hematology), an empty listbox (ListBox1) and my two command buttons (Nothing to Delete and Remove Parameters).


Private Sub Hematology_initialize()
Dim Wrkst As Worksheet
Dim Header1 As Range
HeaderRange1 As String

For Each Wrkst In Worksheets
If Wrkst.Name = "Hematology" Then
For i = 1 To Wrkst.ColumnCount
Set Header1 = Wrkst.Cells(5, i)
HeaderRange1 = Header1.Address & ":" & Header1.Offset(1, LastColumn).Address
With Hematology.ListBox1
'Clear old ListBox RowSource
.RowSource = vbNullString
'Parse new one
.RowSource = HeaderRange
End With
Next i
End If
Next Wrkst
End Sub