Achillea lanulosa var. eradiata (Piper) M.Peck (original description)
Artemisia campestris var. pacifica (Nutt.) M.Peck (original description)
Artemisia vulgaris var. glandulifera (L.F.Hend.) M.Peck accepted as Artemisia indica Willd. (original description)
Artemisia vulgaris var. longifolia (Nutt.) M.Peck accepted as Artemisia longifolia Nutt. (original description)
Aster subg. Oreostemma (Greene) Peck (original description)
Crepis bakeri var. cusickii (Eastw.) M.Peck accepted as Crepis bakeri subsp. cusickii (Eastw.) Babc. & Stebbins (original description)
Crepis occidentalis var. pumila (Rydb.) M.Peck accepted as Crepis occidentalis subsp. pumila (Rydb.) Babc. & Stebbins (original description)
Haplopappus hirtus var. lanulosus (Greene) M.Peck accepted as Pyrrocoma hirta var. lanulosa (Greene) Mayes ex G.K.Br. & D.J.Keil (original description)
Haplopappus hirtus var. sonchifolius (Greene) M.Peck accepted as Pyrrocoma hirta var. sonchifolia (Greene) Kartesz & Gandhi (original description)
Haplopappus uniflorus var. howellii (A.Gray) M.Peck accepted as Pyrrocoma uniflora var. uniflora (Hook.) Greene (original description)
Senecio triangularis var. trigonophyllus (Greene) M.Peck (original description)