On Bl. Arago there is a pedestal which I'm told used to have a statue of Arago.
The way I heard it, the statue was melted down during the Commune to make cannon. I don't know how true this is, however.
Arago helped refine the location of the Paris Meridian (which competed for a long time with the Greenwich one). This was commemorated much later with a series of little markers embedded into the ground at a number of places along this meridian in Paris:
It probably won't surprise anyone that there are a number of statues and portraits of Arago at the Observatoire de Paris.