Of the origins of FIAT Ferroviaria, they say:
In 1906, six trams powered by petrol engines heralded the start of
Fiat's production of rolling stock. A record was soon achieved: in 1924
the world's first diesel-electric railcar was produced to replace the old
steam locomotive.

In 1931 a new railcar was presented, the only one in the world with a
truck-derived power unit that ran first on petrol and then diesel: this
was the famous "Littorina".

And further:
Between the two wars, the train, that public transport vehicle par
excellence, underwent a technological transformation that had been
in the pipeline for years, but was trumpeted by the Fascist regime
as its own historic breakthrough. The "Littorina" (named after the
Fascist emblem) was a high-speed electric train manufactured by
Fiat and introduced onto all the main railway lines in the early thirties.
Its appearance coincided with a modernisation programme that
electrified much of the railway network.
 
 

 advertisement poster
 for FIAT Littorina
Giuseppe Riccobaldi
 Del Bava, 1934

It appears the cover which I had used on the previous page came from Riccobaldi del Bava's works.
advertisement poster
 for FIAT Littorina

advertisement sketch
 for FIAT Littorina
 Model 025 A
 Artist unknown, 1935

  Model 025 A is one of the units built for the Eritrean Railway.  The artist took some license to remove the characteristic double roof.

advertisement sketch
 for FIAT train Model
 007
 M. Caffaro Rorè, 1934