The final part of the series should be the cover he did for his own books - all of which are a study in simplicity.
Satyajit Ray was a prolific writer of short stories. Each collection contained 12 stories and the names were a play on the Bengali words for twelve (baro) or dozen (dojon).
Ek Dojon Goppo (A Dozen Stories), Aro Ek Dojon (One More Dozen), Aro Baro (Twelve More), Ebaro Baro (Twelve Again), Eker Pithey Dui (Two on One) and Bah! Baro (Wow! Twelve).
His second-most popular series was, of course, Professor Shonku. The Shonku series started with mock-seriousness almost bordering on parody in the first story. However, the durability of the character was established with that first story and Ray had to invest a lot of gravitas into the character to make Shonku into a world-renowned, genius inventor.
As a complete contrast to Feluda's modesty, Shonku was immodest in matter-of-fact manner. He had no qualms in calling himself a genius and his adventures took place across the globe. The covers reflected his slight eccentricity as well as the international settings.
I particularly like Swayam Professor Shonku, where his beard and hair are made out of international newspaper cuttings and Punascha Professor Shonku, where his face has the topography of a globe.
And quite obviously, Feluda has to bring up the rear in true 'last but not the least' tradition. The structure of the typical Feluda cover never changed. It had Feluda, Topshe and Lalmohanbabu in the foreground and a distinctive landmark of the story's location looming - sometimes menacingly - in the background.
It would be interesting to see some of the earlier covers - which are also in the same format - though Feluda and Topshe are much younger (and Lalmohanbabu missing).
The first illustration is not a cover but the full-page illustration at the beginning of the first ever short story (when it first appeared in book-form) and Topshe is almost a kid. Interestingly, the first Feluda story also did not envisage the durability of the sleuth and showed Feluda as a hobbyist, who happens to solve a crime while on vacation (from a regular job) in Darjeeling.
When the story first appeared in Sandesh magazine, the illustration on the first page was almost like a caricature!
By the time it was published in Ek Dojon Goppo, a few more stories had already appeared, the Bengali bhadralok had got as hysterical as they could have possibly got and Feluda was on his way to become the highest-read and second-most popular Bengali fictional character ever.
That, I think, caps off this series for the time being.