MUSTARD FAMILY 97 



Septum of the pod nerved, with longitudinal 

 reticulations. 19. Norta. 



I Septum of the pod nerveless, with transverse 



reticulations. 20. Brata. 



Put>escence of forked hairs. 



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



leaves piunatifld or lobed. 21. Sophia. 



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



22. MAtiCOIMIA. 

 tX Pod 4-angled. 



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

 Stem-leaves not clasping. 



Corolla white. 24. Arabidopsis. 



Corolla yellow or purplish. 



Seeds plump; leaf-blades entire or toothed. 



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

 attached near the middle; partition of the pod not 

 cross-veined. 25. Chedbinia. 



Hairs of the stem and leaves spreading, branched, 

 attached at the end; partition of the pod cross- 

 reticvdate. 26. Hesperis. 



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

 ** 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. Eaphanxts. 

 Pods opening by valves, without transverse partitions. 



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

 with an intemode, containing 1 seed. 

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

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

 Beak elongated-conic, seedless. 31. Brassica. 



b. Pod flattened parallelly to the broad partition. 



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

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



uncinate. 32. Athtsanus. 



Fruit winged, usually marked with fenestrations or siuuations on the 

 margin ; pubescence of simple hairs. 33. THTSANOCARPtrs. 



Fruit 2-celIed, 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 fiattened 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. Dentaria. 

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

 Valves not elastically dehiscent; 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. Conbingia. 



Anthers subsagittate at the base. 



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

 bent. 41. Parrta. 

 Stigma entire, capitate; seeds marginless ; cotyledons obUquely 

 accumbent. 42. Phaenicaulis. 

 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. Cabtiera. 

 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. PARRTA. 



Lobesof the stigmas over the valves; annuals. 45. Streptantella. 



