252 Class XV. Order II. 



sword blade, articulated to a knob at the end' of the pedicel, 

 acute, flat, pendulous. Woods, Chelsea beach island. August. 



ARABIS RHOMBOIDEA. Rhomboidal Arabis. 



Leaves smooth, rhomboidal, repand, or obsoletely 

 toothed, the lower ones on long petioles ; root tuberous. 



Root tuberous and farinaceous. The leaves which spring 1 

 from the root are generally heart shaped, the lower stem leaves 

 oblong or ovate, repand, obtuse, smooth ; the upper ones be- 

 coming quite narrow. Flowers white, in a terminal raceme. 

 Peduncles smooth, slender. Calyx of four erect, obtuse leaves. 

 Petals roundish, unguiculate. Anthers sagittate with microsco- 

 pic glands at the base of the filaments. -Wet Meadows, Roxbury. 

 May. Perennial. 



269. RAPHANUS. 



RAPHANUS RAPHANISTRUM. L. Wild Radish. 



Pods round, jointed? smooth, of one cell. L. 



A hardy weed, frequent in the gravel by road sides, but most 

 troublesome in cultivated fields. Stem branching, round, bristly, 

 glaucous. Leaves rough, lower ones lyrate, upper ones toothed. 

 Calyx bristly. Petals spreading, yellow, turning white as they 

 grow old, not unfrequently of a light blue. Pods erect, knobbed, 

 tapering, smooth, ending in a long beak. When dry, they are 

 striated, and abruptly contracted between the cells, which are 

 hard and somewhat bony. On cutting the pod across between the 

 seeds, it appears two celled. The seeds however are contained 

 between the laminae of the apparent partition. 



270. CARDAMINE. 

 CARDAMINE ROTUNDIFOLIA ? MX. Round leaved Cardamine. 



Leaves simple, suborbicuiate, entire ; stems simple, 

 weak, procumbent. 



Caespitose. Stems ascending, branched. Leaves ovate, ob- 

 tuse, submucronated, smooth, on long petioles. Flowers fasci- 

 cled or corymbed. Calyx leaves oblong, obtuse, spreading. Pe- 

 tals oval, subacute. Filaments subulate, hollow above. Capsule 

 linear. -On the highest summit of the White mountains. July. 



