select options question

Right now the select I needed looks like this:

<%= options_from_collection_for_select @states, :id, :name, @canlocation_options[0] %>

I want to add in :prompt => , or :blank => but then I’m exceding the parameters, 5 for 4.
Any maybe this is an HTML question, but is there somewhere I can add in a blank selection ?

TIA
Stuart