It was noticed that there is a minor discrepancy between the gnome supplement and the core rule monster section. I recommended to the group that came across this is to use the core rules as the supplement is considered playtest material.
Core rules: Gnomes stand 3 to 3½ feet tall and weigh 40 to 45 pounds. Their skin color ranges from dark tan to woody brown, their hair is fair, and their eyes can be any shade of blue. Males usually wear short, carefully trimmed beards.
Gnome Supplement: Gnomes are small and stocky, more so than Halflings but not as much as Dwarves; both male and female Gnomes stand around three and a half feet tall and typically weigh around 90 pounds. Their hair and beards may be blond, brown, black, or sometimes red.