Looks like a bellytanker from this angle

Also, a resemblance to the 1917 Golden Submarine of Barney Oldfield

I guess this is a good example of concurrent evolution when form begets function... to slip through the air resistance, most designs will end up the same when built for simplicity and lightweight racing applications

It's likely that the Benz was designed 10-20 years after Oldfields sub, and 10 years before the bellytanks were made into dry lakes racers, so it's well bookended by American hot rodders for good company.