460 



THE COMPOSITE FAMILY. 



In high northern latitudes, or at con- 

 siderable elevations in the mountain- 

 ranges of Europe, Russian Asia, and 

 Arctic America. Frequent in the High- 

 lands of Scotland, and found also in 

 North Wales, in the Lake district of 

 northernEngland, and in Kerry county, 

 Ireland. 



Fig. 549. 



XXIY. THISTLE. CAKDUUS. 



Herbs, with hard stems. Leaves often cut, and usually very prickly. 

 Involucres globular or ovoid, the bracts numerous, closely imbricated, 

 and usually prickly. Receptacle thick, bearing bristles between the 

 florets. Florets all equal and tubular. Achenes glabrous, with a pap- 

 pus of numerous simple or feathery hairs longer than the achene 

 itself. 



The largest and widest-spread genus among Thistle-heads, for al- 

 though the species are chiefly European and Asiatic, yet there are also 

 several from North America, and the common ones accommodate 

 themselves readily even to a tropical climate. They are usually di- 

 vided into two genera, the plume Thistles {Cirsium or Cnicus) with a 

 feathery pappus, and the true Thistles with a simple-haired pappus, 

 but the distinction is so purely artificial that several botanists now re- 

 vert to the old natural limits indicated by Linnaeus. 



Pappus consisting of simple hairs (True Thistles). 



Bracts of the large involucre very broad at the base, 



with lateral as well as terminal prickles . . . . 1. Milk T. 

 Bracts of the involucre lanceolate or linear, without 

 lateral prickles. 

 Involucres globular, large. 



Involucral bracts broadly anceolate 2. Musk T. 



