The key to the genera in Budd's Flora requires the following contradictory or incorrect answers for Melampyrum.  My comments are in red. 

	flowers solitary in the upper leaf axils; NOT [flowers in terminal panicle-like cyme] Contradicts next answer.  Flowers are either solitary in upper leaf axils or in a terminal, leafy spike.
	flowers NOT solitary Contradicts previous answer.  Flowers are either solitary in upper leaf axils or in a terminal, leafy spike.
	flowers blue Flowers are whitish to purplish with a yellowish lower lip.

Melampyrum: The remaining answers to key questions from Budd's Flora, and those from Flora of Alberta, that lead to this genus are as follows.

	stems leafy; NOT [leaves in a basal rosette, stem leafless]
	leaves opposite; NOT [leaves alternate, whorled, or basal]

	leaves with stalks; NOT [upper leaves stalkless]
	leaves 10-40 mm long; NOT [leaves 2-10 mm long]
	leaves linear to lanceolate; NOT [leaves ovate]
	leaves simple, neither lobed nor cleft; NOT [leaves lobed or cleft]
	leaves more or less entire, barely toothed; NOT [leaves sharply and coarsely toothed]
	floral leaves or bracts usually green; NOT [floral leaves or bracts brightly colored, usually red or yellow, or shades of these colors]
	flowers less than 10 mm long; NOT [flowers large and showy, 10-35 mm long]
	calyx much shorter than 1 cm long in flower
	calyx 4-lobed; NOT [calyx 5-lobed]
	calyx not membranous and not much inflated in fruit; NOT [calyx becoming enlarged, membranous, veiny, and inflated in fruit]
	corolla NOT spurred at the base
	four anther-bearing stamens and no sterile stamens
	corolla white to yellow; NOT [corolla pinkish purple]

Scrophulariaceae: Answers to key questions in Budd's Flora  leading to this family. 

	herbs; NOT [shrubs or trees]
	plants green or with some chlorophyll; NOT [plants parasitic or saprophytic, without chlorophyll]
	plants NOT aquatic
	leaves NOT bearing bladders
	stems NOT square
	flowers with two floral rings, but with the petals wholly or partly united forming a tube or bell
	flowers irregular
	flowers brightly colored; NOT [flowers inconspicuous]
	corolla irregular; NOT [corolla regular]
	ovary superior; NOT [ovary inferior]
	fruit a many-seeded capsule; NOT [fruit with 4 nutlets]