MONTREAL—Mount-Royal and Lasalle-Emard, the names are legendary to Quebec’s Liberals, ridings long held by leaders like Pierre Elliott Trudeau and Paul Martin.

Under a proposal made public in July, the federal government could undertake a wholesale redrawing of Quebec’s electoral districts, putting an end to the cherished names of some ridings.

On Friday, Justin Trudeau marched into the Montreal courthouse wearing an open-collared shirt and carrying a large map of the island of Montreal. Followed by a dozen MPs, Trudeau made his case to the Federal Redistribution Commission to save Montreal’s old ridings.

“They want to cut St-Laurent in three, Cartierville in two, they want to put St-Laurent’s industrial park outside the riding,” said an uncharacteristically animated Stephane Dion, the MP for St-Laurent-Cartierville.

“We wanted to be sure that the communities would be respected while at the same time ridings would have about the same number of population.”

While some like NDP MP Helene LeBlanc called for the “status quo,” the commission will need to make changes. Four ridings will be added to the Montreal-area, two in Laval, one in Longueuil and another on island.

"In our opinion, the proposed changes reflect the new reality of Quebec, with the current trend toward higher-density urban centres,” wrote the head of the commission, Jules Allard, in a statement.

On Friday, a number of Liberal MPs presented what they called “improvements,” while asking harsh questions about many of the changes made. In some ridings, landmarks were torn out of ridings they had long been part of, while others were split along streets that MPs found to be “illogical.”

A quiet Irwin Corler listened as changes to his Mount-Royal riding were described. With a member in Parliament since 1925, Cotler would be the riding’s final MP under current plans. A new riding, John-Peters-Humphrey, would swallow much of Mount-Royal.

The new riding names were a serious point of contention.

“They put up a name of Dr. Penfield and the street isn’t even in the riding,” said a blunt Denis Codere, the Liberal MP for Bourassa. A new Wilder-Penfield riding would cover most of Westmount and Notre-Dame-de-Grace.

Doctor Penfield Ave. is in Ville-Marie, near McGill University.

Some MPs were also puzzled at how the new boundaries mixed up socio-economic groups that had long had different representatives, blurring traditionally upper-class ridings by adding working-class neighbourhoods—and vice-versa.

“The socio-economic realties of Park-Extension versus Mount-Royal show that if people in two blocks of Park-Extension are to be represented by an MP who is predominantly in Mount-Royal, there’s a concern they won’t be well represented,” said Trudeau.

The MPs also took pains to point out that their opposition to the new ridings was non-partisan.

“I want to keep the two blocks of Papineau that they are moving to Park-Ex, those are very red blocks,” said Trudeau, referring to the Liberal Party’s colour. “But at the same time I’m also fighting very hard to hold onto the northern section of Villeray, which doesn’t vote for me.”

Hearings continue until mid-November. The changes will take effect before the next election.