partial _form not rendering

I am working through the agile web development with rails and after
generating the pages from the "product" scaffold, the partial within
the new.rhtml file no longer renders to the browser.

Is there something that I am missing here?

Thanks for any help.

(if this is a double post, it is because I posted it 10 min ago and it
didn't show up)

<!-- new.rhtml -->
<h1>New product</h1>

<% form_tag :action => 'create' do %>
  <%= render :partial => 'form' %>
  <%= submit_tag "Create" %>
<% end %>

<%= link_to 'Back', :action => 'list' %>

<!-- _form.rhtml -->
<%= error_messages_for 'product' %>

<p><label for="product_title">Title</label><br/>
<%= text_field 'product', 'title' %></p>

<p><label for="product_description">Description</label><br/>
<%= text_area 'product', 'description' %></p>

<p><label for="product_image_url">Image url</label><br/>
<%= text_field 'product', 'image_url' %></p>

<p><label for="product_price">Price</label><br/>
<%= text_field 'product', 'price' %></p>