Monday night's marathon City Council meeting featured yelling, heated debate, impassioned pleas and a campaign to save the white geese of the Charles River.

What was missing was the expected third round of the mayoral elections. The election was the fifth item on the council's list of unfinished business, but by the time the meeting finally adjourned seven and a half hours after it started, the council still hadn't gotten around to choosing its first leader of the 21st century.

Instead, the council spent several hours deliberating before they approved, with four amendments, the Larkin petition, which will put an 18-month moratorium on development in East Cambridge.

The petition, circulated by resident Shannon Larkin, aims to slow the commercial construction boom in the Kendall Square area. Petition signers say the encroaching firms eliminate green space, push out smaller stores, and bring unwanted traffic.

At last night's meeting, City Manager Robert W. Healy also committed to funding a planning study which will take place in conjunction with the moratorium.

The three Planning Board amendments to the petition passed without opposition. One will exempt housing developments from the moratorium, which halts construction in an area bordered by the Somerville-Cambridge line, First Street, Main Street, and Windsor Street.

The other two will exempt a Southern Energy project site and a proposed office building at 286 Third St.

After Councillor Anthony D. Galluccio proposed a fourth amendment which could allow for the construction of two proposed telecommunications projects, however, things heated up.