  | 
         herbs; NOT [shrubs or trees]  | 
        | 
         plants green or with some chlorophyll;
        NOT [plants parasitic or saprophytic, without chlorophyll]  | 
        | 
         plants without milky juice  | 
        | 
         NOT [twining plants with large,
        funnel-form corolla]  | 
        | 
         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 regular; NOT [corolla irregular]  | 
        | 
         stamens 4 or 5; NOT [stamens 8 or 10]  | 
        | 
         stamens alternating with corolla lobes,
        or twice their number; NOT [stamens directly in front of corolla lobes]  | 
        | 
         style terminal; NOT [style from center of
        lobes of ovary]  | 
        | 
         ovary superior; NOT [ovary inferior]  | 
        | 
         ovary 2-celled; NOT [ovary 1-celled], NOT
        [ovary 3-celled]  | 
        | 
         ovary with seeds borne on axis in center
        of cell; NOT [ovary with seeds born on wall of cell]  | 
        | 
         fruit a berry or a capsule; NOT [fruit
        with 4 nutlets]  |