I like the description in the link Christian provided: "dog at their feet either eating or vomiting". Why would you want a picture of a dog vomiting on a coin??? LOL.
This Rechenpfennig now is reported in 3 varitions with reference GL 198, 199 and 200 in: "Nürnberger Rechenpfennige, Band 2, The Lauffer family". further information: groenendijk.f@planet.nl and http://rechenpfennig.webs.com/newnieuwneunouveau.htm