What constellations are near mercury?
All of the constellations of the zodiac.
The constellations along or near the ecliptic, including the constellations of the Zodiac, are visible from most of north and south america. At high latitudes in either direction, the equatorial constellations will be pretty low on the horizon and may not be visible unless the terrain is fairly flat, or from high elevations such as mountain peaks.
The constellations near the plane of the ecliptic (the zodiacal constellations) are only visible at certain times of the year. The constellations towards the poles (N and S) are visible at all times of the year from their respective hemispheres. In the South, the Southern Cross would be one example and in the North the Great Bear (or plough) would be another.