98 THE CBITCrFEB. TAMILT. 



1. Field Pennycress. Thlaspi arvense, Linn. 

 (Eng. Bot. t. 1659. Pennycress. MitJi/ridate Mustard.) 



An erect, glabrous annual, 6 inches to a foot high or rather more, simple 

 or branched in the uyjper part. Radical leaves stalked, but soon disappear- 

 ing. Stem-leaves oblong or lanceolate, usually marked with a iew coarse 

 teeth ; the lower ones narrowed at the base, the upper clasping the stem 

 with prominent auricles. Pods in a long raceme, about half an inch in 

 diameter including a very broad wing, deeply notched at the top, with a 

 very minute style in the notch. Seeds usually 6 in each cell. 



In cultivated and waste places, throughout Em'ope and Russian Asia. 

 Widely scattered over various parts of Britain, but not so common with us 

 as on the Continent. Fl. spring and summer. 



2. Perfoliate Pennycress. Thlaspi perfoliatiun, Linn. 



(Eng. Bot. t. 2354.) 



A glabrous annual, branching at the base, or nearly simple, the stem 

 ascending or erect, 3 to 6 inches high. Radical leaves spreading or tufted, 

 stalked, ovate or orbicular ; upper stem-leaves ovate or oblong, clasping 

 the stem with rather large, rounded auricles. Pods not half the size of 

 those of the^e^rf P., with narrower wings, and the notch at the top much 

 broader and more open. Style nearly as long, or longer than the notch. 

 Seeds usually 4 in each cell. 



In stony pastures and waste places, chiefly in limestone districts, in 

 central and southern Europe, and temjjerate Russian Asia. In Britain, 

 apparently confined to a few looahties in Oxfordslure and Gloucestershire. 

 Fl. spring. 



3. Alpine Pennycress. Thlaspi alpestre, Linn. 

 (Eng. Bot. t. 81.) 



A glabrous biennial or perennial, forming a shortly-branched or tufted 

 stock, with obovate, oval, or oblong, stalked, radical leaves. Stems simple, 

 erect or ascending, about 6 inches liigh ; the leaves narrow, clasping 

 the stem with small auricles. Flowers usually larger than in the two 

 last. Pod about 3 hues long, but not so broad as in the perfoliate P., 

 especially at the base, the wings rounded at the top, leaving a broad but 

 not a deep notch between them. Style prominent. Seeds 6 or 8 in each 

 cell. 



In mountain pastures, in limestone districts, in central and southern 

 Europe, extending northward to southern Sweden, and eastward to the 

 Russian frontier. In Britain, chiefly in the north of England, but found 

 also in some other parts, as well as in Wales and Scotland. PL shimmer. 

 A slight variety, vidth rather larger flowers, has been distinguished as a 

 species, under the name of T. virens. 



XIX. TEESDALIA. TEESDALIA. 



Dwarf annuals, with white flowers, two petals larger than the two others, 

 as in Candytvft ; but the longer filaments have a scale-like appendage near 

 their base, and the pod has 2 seeds in each cell. 



A genus confined to two European species. 



I 



