Thymiflorum: Answers to key questions in Budd's Flora and Manual of Montana Vascular Plants leading to this species. 

	verticillasters forming an long, loose, interrupted inflorescence; NOT [verticillasters crowded tightly together]
	calyx puberulent; NOT [calyx hirsute]

Dracocephalum: Answers to key questions in Budd's Flora and Manual of Montana Vascular Plants leading to this genus. 

	leaves crenate to serrate; NOT [leaves entire or nearly so], NOT [leaves deeply palmately lobed]
	flowers occur in paired cymes arising from the axils of two oppositely placed leaves (each pair comprising a single verticillaster); NOT [flowers solitary, terminal or in racemes]
	calyx irregular, with one large upper lobe and four smaller lower lobes; NOT [calyx with three upper lobes differing from the lower two]; NOT [calyx regular]
	calyx without hooks at tips of lobes
	upper corolla lip often hood-like, at least partially overarching the stamens; NOT [upper corolla lip not hood-like, not enclosing stamens]
	stamens 4

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

	herbs; NOT [shrubs or trees]
	plants green or with some chlorophyll
	plants not aquatic
	stems square
	leaves opposite
	leaves not bearing bladders
	flowers not in heads or spikes; NOT [flowers in long or short spikes], NOT [flowers in heads or in form resembling a head]
	flowers with two floral rings
	petals wholly or partly united forming a tube or bell
	corolla irregular; NOT [corolla regular]
	ovary superior; NOT [ovary inferior]
	fruit with 4 nutlets; NOT [fruit a many-seeded capsule]