Where are form submission being stored?

Hello,

I have a form installed. Code as follows:

<perch:form id="contact" method="post" app="perch_forms">

<perch:input type="textarea" id="message" required="true" label="Message" />
<perch:input type="submit" id="message" required="true" label="Submit" />

<perch:success>
  <perch:content id="thankyou" label="Success message" type="textarea" textile="true" editor="markitup" />
</perch:success>

</perch:form>

The form displays and submits OK, I get the success message afterwards. However I cannot see where the results of the form submission are being sent/stored.

The Back end says "No forms have been submitted yet. Submit a new form to have it show up here."

Could you explain how this works please or if there are any attributes I am missing anywhere.