Bianchi Thomisus sizing
 

hi,
i would like to know how the sizes of an old MTB bianchi thomisus really work (and in general in that range of bianchi´s 90´s MTB: theridion, ragno, etc.)
i mean of course in what sizes they were originally offered, but also what do these seizes mean (do e.g. a size 50 on these old MTBs actually mean 50cm center to center? and would this correspond to the standard road bike size 50?) i would very mach apreciate some orientation with that...

thanks in advance!

here´s a photo from the internet:
https://cloud10.todocoleccion.online...7/63119688.jpg

I´ve found all the information i was looking for in an italian facebook site: "Biciclette Bianchi Ragno" lots of information, pictures, catalogues, etc.
just in case there is also someone searching for more info on this bike.

https://cimg2.ibsrv.net/gimg/bikefor...72ae60bc9d.jpg

Holy Triple Triangle, Batman!!!

How did I miss this? Bianchi USA cataloged one in ‘90 called the Signature 2 but I’m not sure any were imported.
https://cimg2.ibsrv.net/gimg/bikefor...63714da8c.jpeg