Stutz's Monte Carlo was a "close-coupled" four-door sedan. That is, although there was seating for at least four people, the passenger compartment was shorter than normal. At the likely price of restricted back-seat legroom, the style effect was racier than normal.
A noteworthy feature was a trunk profile years in advance, as will be shown below -- an early instance of a sedan with "bustle back" styling.
Monte Carlo bodies (1929-1933) were by the Weymann licensee Weymann American Body Company of Indianapolis, Indiana, where Stutz also was based. As the link explains, the Weymann system made use of wood structuring that included flexible joining, along with padded cladding with a synthetic leather protective layer. The link also lists advantages of the Weymann system. Defects included minimal collision protection and shorter useful life compared to metal-clad bodies. By the early 1930s, Weymann bodies were rapidly falling out of fashion.
In terms of styling, a Weymann defect was that the protective layer was not smooth, not shiny. Sort of like the matte paint finish occasionally seen in recent times.
Most Stutz Monte Carlos had Weymann system bodies. But at least one 1933 Monte Carlo had aluminum cladding, even though it was built by the Indianapolis Weymann firm.
I do not know who styled the Stutz Monte Carlo.
1930 Cadillac Town Sedan - car-for-sale photo
I don't have a decent side view of a 1930-vintage Stutz sedan, so this Cadillac photo will serve to indicate the upscale sedan styling norm for that time. Note that the aft side of the passenger compartment is nearly vertical. There is no integral trunk, instead a detached one.
1929 Stutz Blackhawk Doctor's Coupe - Donnington Auctions (New Zealand)
On the other hand, coupes and roadsters did have "bustle backs," often featuring a rumble seat. So this concept was available for sedan styling, but essentially not used at the time.
1929 Stutz Lancefield Saloon - via coachbuild.com
British coachbuilder Lancefield made several bodies for Stutz's. This is an early example that used Weymann technology. Note the modest bustle back.
1929 Stutz Monte Carlo by Weymann (Indianapolis) - Bonhams
Here is an early Monte Carlo of the same vintage. It features a bustle back with nearly the same profile as that on the Lancefield. I don't know which design was came first. Regardless, these are the earliest examples of bustle back sedans that I'm presently aware of. There might well be earlier examples, so please let us know in Comments.
1930 Stutz Monte Carlo by Weymann (Indianapolis) - via RM Sotheby's
A beautifully restored Monte Carlo. The beltline two-tone strip enhances the already impressive length. The passenger compartment greenhouse is low, proving a racy appearance (compare to the more standard greenhouse on the Cadillac in the first image above).
The lower body is massive, helping to contrast and enhance the low roofline.
Even though the bustle back contains trunk space, this car has an auxiliary, detached trunk.
1933 Stutz Monte Carlo by Weymann (Indianapolis) aluminum body - via RM Sotheby's
A very late Monte Carlo example.
The metal cladding provides smooth surfaces for paint. I find the result much more attractive than the dull-finish Weymann paint jobs.
No extra trunk here. The bustle back feature gives the car a more modern appearance than other 1929-origin American sedan designs.