Centaurea.'] xlvi. composite: ctnarocepiial^e. 241 
rows in our var. /8. is often so long as not to be covered by the outer 
scales, a structure we have never seen in var. a. Pappus perhaps never 
entirely wanting, usually consisting of an outer row of very short 
blunt scales, and in var. a. of numerous longer ones which are often 
deciduous; these longer ones in our var. /3 seem either to be few in 
number, or entirely wanting. We have no objection to unite the 
rayed form to the last, as we are not aware that cultivation has ever 
caused it to lose its ray, or the common state of C. nigra to obtain one. 
** Involucral scales lanceolate, their upper half with a scarioug decurreqt 
margin. 
4. C. Scabiusa L. (greater K .) ; scales of the involucre ad- 
pressed with a black pectinate margin, leaves roughish pinna- 
tifid, segments lanceolate acute, pappus pilose about the length 
of the achene. E. B. t. 56. 
Barren pastures, corn-fields, and road-sides. Rare in Scotland. 
g . 7 — 9. — Stem 2 — 8 ft. high, erect, much branched. Involucres 
globose, very large; their scales usually cottony, with an almost black 
scarious margin, and paler fringe. Within the outer hairs of the 
pappus there is an inner row of shorter hairs. 
5. C. CyanusL. (Corn B.) ; scales of the involucre adpressed 
with a brown toothed margin, leaves linear-lanceolate entire, 
the lowermost toothed or pinnatifid, pappus pilose rather 
shorter than the achene. E. B. t. 277. 
Corn-fields, frequent. ©. 6 — 8. — Stem 2 — 3 feet high. Covered 
with a loose cottony down, especially on the stems and under-side of 
the leaves. Florets of the disk small, purple; of the ray few, larger, 
bright blue, spreading. Scales of the involucre greenish, their mar- 
gins brown. Outer row of the hairs of the pappus tawny, innermost 
white. 
*** Involucral scales with palmate or pinnated spines. 
6. C. Isnardi L. (Jersey S.) ; scales of the involucre with 
palmate nearly equal spines, leaves scabrous, lower ones some- 
what lyrate or incise-tootked amplexicaul, upper linear coarsely 
toothed tapering at the base, heads terminal solitary with one 
or more leaves at the base. E. B. t. 2256. C. aspera L. 
Pastures in Jersey and Guernsey. H-. 7, 8. — Flowers purple. 
Spines of the involucre small, nearly equal in size. Pappus present in 
all the florets. 
7. C. Calcitrapa L. (common S .) ; scales of the involucre 
glabrous ending in a long broad strong canaliculate spine 
spinulose at its base, stem divaricated, leaves unequally pin- 
natifid spinuloso-dentate, heads lateral solitary sessile, pappus 
none. E. B. t. 125. 
Gravelly, sandy, and waste places, in the middle and S. of England, 
especially near the sea. 0. 7, 8. — Flowers purple. — The specific 
name is derived from an old Celtic and now English word trap, a 
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