48 CRUClFERyE; 



with a fluit, two-edged, sword-likc beak. — Waste ground. — Fl. June, 

 July. Annual. Seedlings of this species are largely eaten, with 

 those of Cress {Lepii/iiu/i sativum), as salad. 



14. DiPLOTAXis (Rocket) has spreading sepals : but differs from 

 the mustards in its flattened pods with membranous valves and 

 studs in two rows. (Name from the Greek diplos, double, taxis, 

 rank or row.) 



r. D. tcniiijltlia (Wall Rocket). — Slender, branched, i — 2 feet 

 high; stem woody below; leaves deeply divided into long narrow 

 segments, glaucous ; piaiuers \ in. across, light yellow, fragrant ; 

 pods short, linear, erect, on very long slender stalks. — On old 

 walls. — Fl. June — .September. Perennial. 



2. D. inuydlis (Sand Rocket), a less^ branched, hispid, herba- 

 ceous, and generall)' annual species, .grows m waste ground, 

 es|iecially near the sea. 



*i5. AlyssUiM, a genus of small plants, mostly hoary with 

 adpressed hairs, with simple leaves, small white or yellow _//i??C't7'5, 

 and rounded, few-seeded pods, includes three alien species, 

 sometimes naturalised : A. inediiuin, A. alyssoides, with stellate 

 hairs; yellow y/^.'jfv/'.f, and persistent sepals : and .'i. inaritivnim, 

 with bi-parlite hairs ; white, sweet-scented //('zt'c/'.f, and deciduous 

 sepals. 



16. DR.-iHA ("\\1iitlow-grass). — Small herbs, mostly perennial 

 and hoary witli stellate liairs ; leaves small, simple, the radical 

 ones in a rosette ; plo:aers small, white of yellow ; pods compressed 

 or turgid. (Name from the Greek drabe,' rcuCi.) 



* I'linvers white 



1. D. mural is (Speedwell-leaved Whitlow-grass). — Stem leafy, 

 branched, about a foot high ; leaves rough, with stellate hairs, 

 egg-shaped, blunt, toothed, embracing the, stem ; pedicels spreading 

 horizontally. — Limestone hills in the west of England ; rare. — 

 Fl. April, May. Annual. 



2. D. inedna (Twisted \Vhitlow-grass); — Stent leafy, branched, 

 4 — 14 in. high; leeives hoary with stellate down, lanceolate, 

 toothed ; /('<•/.? twisted. — Mountains, and sandhills near the sea; 

 uncommon. — Fl. June, July. Perennial. 



3. D. rupi-stris (Rock ^\'hitlow-grass).•^.S'/t7//.f several, i — 2 in. 

 high, almost leafless ; leaves rosulate, stellately pubescent, ciliate. 

 — In crevices of the rocks and among moss on the summits 

 of some Highland mountains; very rare. — 1^1. luly, August. 

 Perennial. 



