I will search again, but I am certain that the code  I am starting
with and trying to understand does not have anything equivalent to
your line  below that I marked with **** -- no declaration/dim in the
main routine

The only places I can find the variable  in question are marked below
by $$$$$$ -- except all places where $$$$ appears is the SAME
symbol, not two different ones as you show.

I changed the variable names below to represent what I have (that is
working). My original post has the code as well.

It appears that this is an "Implicit" way to *both* define a
global/Public variable AND pass it by reference (address) - *in* the
sub entry point. There is a type declaration in the sub entry
statement as I show.

I am still a little shaky on the definitions of "By Ref" and "By
Value" If I think hard...
By Ref="Here's the address, go ahead and muck about with my variable".
By Value = "Here's my value (a copy). You know what it is, but I'll
keep my variable intact.