Police said the heated exchange occured when the taxi driver had refused to ferry the woman and her son. The man turned violent and assaulted them.
The other taxi drivers who gathered at the spot too abused and manhandled them.
A mobile police party intervened and arrested one of the drivers, the police said adding the mother and son were administered first aid at the hospital.
An errant driver of an autorickshaw was arrested yesterday four days after a four-year-old gold fractured her left leg and was seriously injured after falling off her mother's lap from the overcrowded and speeding vehicle at Sinthee area in Kolkata.
The driver had paid no heed to the mother's pleadings to stop and finally stopped 30 metres off the area.