394 TETRADYNAMIA SILICULOSA. 



cells many-seeded ; seeds not margined ; cotyleaons accumbent \*Jilam. 

 without teeth. 



290 LEPIDIUM. Silicle ovate or subcordate; \alvescarinate, dehis- 

 *nt ; cells 1-seeded ; cotyledons incumbent. 



SILIQUOSA. 



291. DENT ARIA. Silique lanceolate; valves flat, nerveless, often 

 opening elastically ; receptacles not winged ; funiculus dilated ; seeds 

 in a single series, ovate, emarginate ; cotyledons accumbent. 



292. CARDAMINE. Silique linear, with the margins truncate; 

 valves flat, nerveless, often opening elastically, narrower than the 

 dissepiment ; seed not margined, with a slender funiculus. 



293. ARABIS. Silique linear ; valves flat, 1-nerved; seeds in a single 

 row ; cotyledons accumbent ; cal. erect. 



294. BARB AREA. Silique 4-edged; cotyledons accumbent ; seeds in a 

 single row ; cal. equal at the base, erect ; shorter filaments with in- 

 termediate glands. 



295. NASTURTIUM. Silique subterete, often short ; valves concave, 

 nerveless, not carinate; cal. equal, spreading; cotyledons accum- 

 bent. 



296. SISYMBRIUM. Silique subterete ; cotyledons incumbent, some- 

 times oblique, flat ; cal. mostly spreading, equal at the base. 



297. SINAPIS. Silique subterete, 2-valved ; (sometimes of 2 articula- 

 tions, of which the upper one is nerveless ;) cotyledons conduplicate ; 

 seeds globose, in a row ; cal. spreading. 



298. POLANISIA. Cal. 4-leaved, spreading ; pet. 4, unequal ; stam. 8 

 32 ; silique sessile in the calyx. 



TETRADYNAMIA. 



SILICULOSA. 

 Species. 288. THLASPI. Penny-cress. 



T. arvense : leaves oblong-sagittate, coarsely toothed, smooth ; silicic 

 suborbicular, longer than the pedicel ; its wings dilated longitudin- 

 ally. 



HAB. Fields. June, <v) ; stem erect, 8 12 in. high, leav. smooth ; 

 fl. wh. 



T. bursa-pastoris : silicic triangular-obcordate, without wings ; cells 

 many-seeded ; radical leaves pinnatifid. 



* The cotyledons are accumbent when the back of one of them is applied to the 

 :urved radicle ; incumbent when the edges of the cotyledons are applied to it. 



