64 CRUCIFERiE. TiiLASPi. 



Tribe VI. THLASPIDE^. DC. 



Silicle dehiscent, compressed contrary to the very narrow septum ; valves boat-shaped. 

 Cotyledons plane, accumbe?it, contrary to the septum. 



12. THLASPI. Dill. ; Endl. gen. 4885. penny CHESS. 



[From the Greek, thUto to flatten ; probably from the compressed form of its seed-vessel.] 



Silicle eraarginatc at the apex ; valves winged on the back ; cells 2- or many-seeded. Petals 

 equal. Calyx equal at the base. — Flowers white. 



1. Thlaspi arvense, Linn. Mithridate Mustard, or Penny Cress. 



Leaves oblong, toothed ; silicles orbicular-obovate, shorter than the pedicels ; style scarce- 

 ly any. — Pursh, fl. 2. p. 435 ; DC. prodr. 1. p. 175 ; Hook.fl. Bor.-Am. 1. p. 58; Torr. 

 ^ Gr.fl.N.Am. 1. p. 113. 



Cauline leaves somewhat sagittate ; auricles minute. Valves of the silicic much com- 

 pressed, furnished with a conspicuous wing. 



In the State of New- York {Fursh). I have never seen specimens of this plant collected 

 within the limits of the State. It is doubtless an introduced species in North America. 



Tribe VII. LEPIDINEJE. DC. 



Silicle usually dehiscent, compressed contrary to the narroiv septum {sometimes \ -celled) ; 

 valves boat-shaped, or rarely ventricose. Cotyledons plane, incumbent, parallel to the 

 septum. 



13. LEPIDIUM. R. Br. in hort. Kew. 4. p. 85 ; Endl. gen. 4932. PEPPER-WORT. 



[From the Greek Icpis, a scale; the fruit being in the form of little scales.] 



Silicle ovate or somewhat cordate ; valves carinate or rarely ventricose, dehiscent ; cells one- 

 seeded. Seeds compressed, or somewhat 3-sided. Flowers small, white. 



1. Lepidium CAMPESTRE, i2. .Br. Mithridote Pepper-iDort. 



Silicles ovate, winged, emarginate, scaly-punctate ; cauline leaves sagittate, denticulate. — 

 DC. syst. 2. p. 535 ; Torr. <^ Gr.fl. N. Am. l.p. 115. Thlaspi campestre, Linn. 



Annual or biennial. Plant 8-12 inches high, simple, or paniculately branched above, 

 clothed with a short soft and mostly simple pubescence. Racemes much elongated in fruit; 

 pedicels diverging horizontally. Silicles 3 lines long. 



Waste places and road-sides ; rather rare. Long Island and Staten Island. Introduced. 

 June - July. 



