Interesting piece of automotive history. The Tatra was a revolutionary, Czechoslovakian made, aerodynamic automobile that was introduced in 1936. Designed by Hans Ledwinka, it was the pioneer of air-cooled, rear-engine autos and was way ahead of it's time with features like aerodynamic styling and four wheel independent suspension. Dr. Ferdinand Porsche based the VW Beetle's pancake, four cylinder, air-cooled engine on the Tatra and the 1948 American made Tucker featured a similar Cyclops third headlight and an air-cooled, pancake rear-engine.  The large rear air scoops on the Tatra cooled the engine. Note the elegant "dorsal" fin. Photographed at the Marin Sonoma Concours d' Elegance.