COMPOSITE. 



463 



3. Welted Thistle. Carduus acanthoides, Linn. (Fig. 552.) 

 (Eng. Bot. t. 973.) 



Much resembles the mush T., but is* 

 usually taller and rather more branched ; 

 the leaves narrower and more prickly ; 

 and the stem more thickly covered with 

 prickly appendages, decurrent from the 

 base of the leaves. Flower-heads not so 

 large, though yet globular and slightly 

 drooping ; the involucral bracts very 

 numerous and narrow, ending in a 

 linear, spreading or recurved prickle, 

 the innermost often of a thinner texture, 

 slightly coloured and scarcely prickly. 

 Hairs of the pappus simple. 



A very common Continental Thistle, 

 extending eastward entirely across Asia, 

 and northward to the Arctic Circle, 

 although in Britain, like many others, 

 it becomes scarce in Scotland. FL sum- 

 mer. Two forms are often distinguished 

 as species, the C. acanthoides, with the flower-heads single, on long 

 peduncles, and the leaves often nearly glabrous, and C. crisjpus, with 

 the heads clustered several together on short stalks, and the leaves 

 usually rather broader and more cottony underneath ; but they run 

 too much one into the other to be separable even as permanent varie- 

 ties. 



Fig. 552. 



4. Slender Thistle. 



Carduus pycnocephalus, Jacq. 

 (Fig. 553.) 



(C. tenuiflorus, Eng. Bot. t. 412.) 



A stiff annual or biennial, from 1 to 3 or 4 feet high, but not so stout 

 as the last three, and much more covered, especially the stems and the 

 under side of the leaves, with a white loose cotton. Leaves pinnatifid, 

 with short, wavy, very prickly lobes, and decurrent along the stem, 

 forming waved prickly wings as in the welted T. Flower-heads rather 

 numerous, but small and ovoid or oblong, generally in clusters at the 

 top of the stem and branches. Involucral bracts rather broad at the 

 base, ending in a narrow, straight or slightly spreading prickle. Florets 



