Hummel and Nashorn/Hornisse: German Self-Propelled Artillery in World War II. David Doyle. 9" x 9". The Hummel ("bumblebee") and Nashorn ("rhinoceros") are two of Nazi Germany's most widely recognized self-propelled artillery pieces. The Hummel, with its heavy field howitzer, was indispensable as heavy field artillery despite its open-top fighting compartment.