[h-e-w] describe-font and "no matching font" message in v21.2.1

[Moore, Mathew L]

I vaguely recall that previously I could use 

  M-x describe-font <RET> <RET>

to get the full name of the current font I am using.  However, when I do
this in version 21.2.1, I get the message

  "No matching font."

I am now supposed to specify a font name?  If so, how do I do this?  I tried
just typing "Courier" and "courier" but I get the same message.  Maybe I am
using the wrong command?

Once again, your help is greatly appreciated.  

Thanks,
--Matt