40 . CRUCIFER.E. 



24. BRASSICA (Cabbage). Pod nearly cylindrical, 

 beaked; valves 1 -nerved; seeds globose, in a single row; 

 calyx erect. (Named from the Celtic Bresic, a cabbage.) 



25. SINAPIS (Mustard). Pod nearly cylindrical, taper- 

 ing, beaked; valves with. 3 or 5 (rarely one) nerves; seeds 

 globose, in a single row; calyx spreading. (Name from 

 the Greek sindpi, mustard.) 



26. DIPLOTAXIS (Eocket). Pod flattened; valves 1- 

 nerved ; seeds oblong, in two rows ; calyx spreading. 

 (Name in Greek, denoting two-rowed.) 



ft Pod without valves. 



27. EAPHANUS (Eadish). Pod swollen, imperfectly 

 jointed, tapering ; seeds globular ; calyx spreading. 

 (Name in Greek, denoting early appearance or quick 

 growth.) 



1. THLASPI (Penny Cress). 



1. T. arvense (Mithridate Mustard, or Penny Cress). 

 Pouch round, flat, with very broad wings, and a deep 

 notch ; seeds striated ; leaves oblong, arrow-shaped at 

 the base, toothed, smooth. In cultivated or waste 

 ground, but not common. Penny cress derives its name 

 from the resemblance which its seed-vessels in size and 

 shape bear to silver pennies ; its longer name it received 

 from having been "formerly used in the Mithridate 

 confection, an elaborate hodge-podge, now laid aside." 

 Sir J. E. Smith. The flowers are white, and very small 

 in comparison with the pouches. Fl. all the summer. 

 Annual. 



2. T. perfoliatum (Perfoliate Penny Cress). Pouch 

 inversely heart-shaped ; style shorter than the notch of 

 the pouch ; seeds 3 to 4 in a cell, smooth ; stem-leaves 

 oblong, heart-shaped at the base. Limestone pastures 

 in Oxfordshire and Gloucestershire, but rare. Flowers 

 white. FL April, May. Annual. 



3. T. alpestre (Alpine Penny Cress). Pouch in- 

 versely heart-shaped, abrupt; style longer than the 



