COMPOSIT 25 
41. ECHINOPS, L. 
Flowers all bisexual; capitules 1-flowered, united into 
a globular head with a common receptacle; involucral 
bracts hard, keeled, shining. Not alpine. 
E. spherocephalus, L.; flowers pale blue, stem 3-5 
ft., with a single globular head, or several; road-sides; 
Western Switzerland, Dauphiny, occasional. 
42. SILYBUM, Geertn. 
Flowers bisexual; outer involucral bracts spiny; pap- 
pus deciduous, formed of several rows of denticulate 
hairs; filaments connate into a sheath. Not alpine. 
S. Marianum, Geertn., Milk-Thistle; involucral bracts 
reflexed, leaves very large, spiny, spotted with white; 
waste places; Valais, but often introduced. 
43. ONOPORDON, L. 
Flowers bisexual, purple; capitules very large; involu- 
cral bracts spiny, webbed; anther-cells tailed; pappus 
composed of ciliate hairs, deciduous. Not alpine. 
O. Acanthium, L.,Cotton-Thistle; stem strongly winged, 
leaves large, very spiny; waste places. 
44. CIRSIUM, Tourn. (Cyzcus, L.). 
Flowers bisexual, usually purple; capitule usually 
globular, involucral scales very stiff, acuminate or spiny ; 
receptacle covered with bristles; pappus feathery; leaves 
spiny. The species appear to hybridise freely. 
Several very common species of Thistle belong to this 
genus, viz.:—C. lanceolatum, Scop., Spear-Thistle, and 
