Instructions
Examine the color of the mushroom cap. The mushroom earned its "jack-o'-lantern" name from its bright orange color. Jack-o'-lantern mushrooms are often more orange than the slightly-yellow chanterelle mushroom.
Lift the cap so you can see underneath. The underside of a jack-o'-lantern mushroom cap has true gills, which are not forked and appear knife-like. As a comparison, chanterelles have false gills on the bottom of the cap, which appear to be folded wrinkles that are forked and look melted together. (See Ref 1 and 2)
Smell the mushroom. Jack-o'-lantern mushrooms are known for their pleasant, fruity aroma, which can entice people to taste them, only to later make them sick. Chanterelles have a similar scent. (See Ref 2)
Examine where the mushroom you want to identify is growing. If it is growing at the base of a tree or on a stump, it could be either a chanterelle or a jack-o'-lantern mushroom (See Ref 2). However, jack-o'-lantern mushrooms can grow in grassy areas where there are no trees, while Chanterelles cannot.
Determine if the mushroom is growing in a large cluster with attached stems, which is how jack-o'-lantern mushrooms thrive. This is a primary method of telling jack-o'-lanterns apart from chanterelles, as chanterelles grow individually or in small bunches with separate stems.
Take one of the mushrooms into a dark area or wait until night fall. Some types of jack-o'-lantern mushrooms glow slightly green in the dark when fresh.