252 TKTRADYNAMIA — SILIOUOSA. [Ttirritis. 



much in size and luxuriance, according- to soil and situation ; from 4 

 iiiclics to 1 foot and more in height, as in C. si/lvatica of authors. 

 Leajicts more or less angled or toothed, upper ones ovate or even linear ; 

 hairy or glahrous. Flowers small, white. 



.5. C* heUidifolia, L. (Daisy-leaved Bitter -cress); leaves sim- 

 ple ovate entire upon rather long footstalks. E. Sot. t. 2355. 



Scotland, {Mr Milne, m With.) County of Clare? — Not a native. 

 Fl. Aug. If. — 1 — 3 inches high. Flowers white. 



19. Arabis. Linn. Rock-cress. 



1. A. stricta, Huds. {^Bristol Bock-cress); leaves toothed ob- 

 tuse hispid, radical leaves somewhat lyrate, stems hairy, petals 

 and pods erect. E. Bot. t. 614. 



Rare ; St Vincent's rocks, near Bristol ; among limestone. Fl. 

 March. If. — Habit of Sisi/mbrium thcdianian, but perennial: root- 

 leaves strongly ciliated, with frequently forked or trifid seta;, and rather 

 hispid than hairy : flowers twice the size ; stem-leaves few, small. 



2. A. petrcea, DC. (alpine Rock-cress); radical leaves lyrato- 

 pinnatifid stalked, cauline ones undivided sessile, pods spreading 

 twice as long as the pedicels. — A. hispida, L. — Cardamine pe- 

 trcea, Huds. — C. Iiastulata, E. Bot. t. 409. 



Alpine rocks in North Wales. Frequent on the high mountains of 

 the vvcst and north of Scotland ; on the Cairngorum range. Hebrides ; 

 especially Skye. Ross-shire and Sutherland, Prof. Graham. Fl. June, 

 July. If. — 3 — 6 inches high, slender, glabrous or more or less hairy. 

 Flowers moderately large, with a purjilish tinge. 



3. A.cilidta, Br. (fringed Rock-cress); leaves somewhat tooth- 

 ed oval glabrous ciliated, radical ones nearly sessile obtuse, 

 those of the simple stem semiamplexicaul. — Turritis alpina, L. — 

 E. Bot. t. 1746. 



By the sea-side at Rinville, Cunnamara, Ireland. Rocks near Loch 

 Lea'in Glen Esk, Scotland. Fl. July. $ . — 4 — 6 inches high. Root- 

 leaves several, oval, or obovato-oblong, obtuse ; cauline ones small. 

 Pods nearly erect. 



4. A. hirsuta, Br. (hairy Rock-cress); leaves all hispid den- 

 tate, cauline ones semiamplexicaul, pods straight. — Turritis 

 hirsuta, L. — E. Bot. t. 587. 



Walls, rocks and banks : frequent in many parts of England and 

 Scotland. Fl. June. $ . — One foot or more high, erect, stiff. Stem 

 rough with spreading hairs, bearing many leaves. Flowers small, white. 

 Pods numerous, erect. 



5. A.*Turrita, h. (Tower Wall-cress); leaves amplexicaul, 

 pods recurved flat and linear with the margins incrassated, brae- 

 teas foliaceous. E.Bot.t. 178. 



WalL of Trinity and St. John's Colleges, Cambridge ; and Magdalen 

 College, Oxford. Cleish Castle, Kinross. Fl. May. $ . 



20. Turritis. Linn. Tower-Mustard. 

 1. T. glabra, L. (long-podded Toiver-Mustard); radical leaves 



