e pod --59.

57a. Calyx pubescent; the pods reflexed =Rock Cress, Arabis holboellii.=

57b. Calyx glabrous; the pods spreading or ascending --58.

58a. Basal leaves densely pubescent
=Rock Cress, Arabis brachycarpa.=

58b. Basal leaves smooth or nearly so
=Rock Cress, Arabis drummondii.=

59a. Petals conspicuous, about twice as long as the calyx, or longer;
straight, erect, mostly unbranched plants --60.

59b. Petals inconspicuous, equaling or but little longer than the calyx
--61.

60a. Pods 3-4 cm. long, ascending (summer)
=Rock Cress, Arabis patens.=

60b. Pods 8-10 cm. long, recurved (late spring)
=Rock Cress, Arabis laevigata.=

61a. Pods widely spreading; stem usually sparingly branched near the
base (spring) =Rock Cress, Arabis dentata.=

61b. Pods erect or appressed; stem usually unbranched (summer) --62.

62a. Stem-leaves and stem smooth and glaucous
=Rock Cress, Arabis glabra.=

62b. Stem-leaves and stem almost always pubescent, and never
glaucous =Rock Cress, Arabis hirsuta.=

63a. Principal stem-leaves 7-10 cm. long, or more --64.

63b. Principal stem-leaves 2-5 cm. long --65.

64a. Leaves lanceolate or oblong; flowers 10 mm. wide or less (3-7
dm. high; summer) =Rock Cress, Arabis canadensis.=

64b. Leaves ovate or ovate-lanceolate; flowers 15-20 mm. wide (5-8
dm. high; late spring and summer)
=Dame's Rocket, Hesperis matronalis.=

65a. Basal leaves ovate to orbicular or cordate, not more than twice as
long as broad (1-3 dm. high; spring) (Bitter Cress) --66.

65b. Basal leaves oblong, lanceolate, or oblanceolate, at least 3 times
as long as broad (1-3 dm. high) --67.

66a. Flowers purple or rose color
=Bitter Cress, Cardamine douglassii.=

66b. Flowers white =Bitter Cress, Cardamine bulbosa.=

67a. Basal leaves pinnatifid (spring and summer)
=Rock Cress, Arabis lyrata.=

67b. Basal leaves entire or toothed --68.

68a. Leaves narrowly oblanceolate; rare plant occurring from
Ma