ML'STARD FAMILY 97 



Septum of the pod nerved, with longitudinal 



reticulations. 19. Norta. 



Septum of the pod nerveless, with transverse 

 reticulations. 20. Br ATA. 



Pubescence of forked hairs. 



Flowers pedicelled, yellow to straw-colored, rarely white: 



leaves pinnatifld or lobed. 21. Sophia. 



Flowers sessUe, rose or white; leaves toothed or entire. 



22. Malcolmia. 

 tt Pod 4-angled. 



Stem-leaves clasping by a cordate base. 23. Conrixgia. 

 Stem-leaves not clasping. 



Corolla white. 24. Arabidopsis. 



Corolla yellow or purplish. 



Seed.s plump; leaf-blades entire or toothed. 



Hairs of the stem and leaves appressed, 2-branched, 

 attached near the middle; partition of the pod not 

 cross-veined. 25. Cheirixia. 



Hairs of the stem and leaves spreading, branched, 

 attached at the end; partition of the pod cross- 

 reticulate. 26. HE3PERIS. 

 Seeds flat; leaf-blades pinnatifld. 27. Campe. 

 ** Pod with a long distinct beak. 



Pods indehiscent, constricted between the seeds, which are separ- 

 ated from each other by false, spongy, transverse partitions. 



28. Raph.\xus. 

 Pods opening by valves, without transverse partitions. 



Beak flat and sword-like, 4-angled, or two-edged, contiguous 

 with an internode, containing 1 seed. 

 Valves of the pod with 3 strong nerves. 29. SiXAPls. 

 Valves of the pod with 1 strong nerve. 30. Eruca. 

 Beak elongated-conic, seedless. 31. Brassica. 



b. Pod flattened parallelly to the broad partition. 



Fruit orbicular, 1-celled, 1-seeded, indehiscent; sepals somewhat spreading. 

 Fruit not winged; pubescence of branched hairs, those of the fruit 



uncinate. 32. Athysaxus. 



Fruit winged, usually marked with fenestrations or sinuations on the 

 margin ; pubescence of simple hairs. 33. Thysaxocarpus. 



Fruit 2-celled, 2-several-seeded, dehiscent (in some species of Draba 

 tardily so) ; sepals erect. 

 Pod orbicular. 



Valves convex; filaments dilated and toothed near the base; plants 

 stellate, leafy. 

 Pod suborbicular, with flat margins; petals entire or nearly so. 



34. Alyssum. 

 Pod oblong, slightly if at all compressed; petals notched. 



35. Berteroa. 

 Valves flat; filaments not toothed; plant scapose, with simple hairs. 



36. IDAHOA. 



Pod oblong, ovate or linear, rarely nearly orbicular; valves flat, or if 

 convex not with flattened margins; filaments unappendaged. 

 Valves nerveless. 



Valves elastically dehiscent; seeds in one row; pod long. 



Stem naked below, 2-3-leaved; cotyledons thick, very un- 

 equal. 37. DEXT.'VEIA. 

 Stem leafy; cotyledons flat, equal. 38. Caedamixe. 

 Valves not elastically deliiscent; seeds in two rows; pod usually 

 short. 39. Draba. 

 Valves nerved and reticulate, not elastically dehiscent. 

 Anthers not subsagittate at the base. 



Pod short, from orbicular to linear-oblong. 



39. Draba. 

 Pod elongated-linear. 



Cotyledons accumbent. 40. Arabis. 



Cotyledons incumbent. 23. CONKINGIA. 



Anthers subsagittate at the base. 



Stigma 2-lobed; seeds margined; cotyledons strictly accum- 

 bent. 41. Parrta. 

 Stigma entire, capitate; seeds marginless; cotyledons obliquely 

 accumbent. 42. Phaexicaulis. 

 2. Anthers sagittate at the base. 



Calyx urn-shaped, closed; blades of the petals narrow, undulate-crisp. 

 Cotyledons accumbent; stem not succulent; flowers small. 



43. Cartiera. 

 Cotyledons incumbent; stem more or less succulent; flowers comparatively 

 large. 44. Caulanthus. 



Calyx campanulate, open; petals ample. 



Pod flat; anthers neither curved nor twisted. 

 Stigma 2-lobed. 



Lobes of the stigma over the placentae; perennials. 



41. Parry A. 

 Lobes of the stigmas over the valves ; annuals . 45 . Strept axtella . 



