loO 
46. COMPOSIT.E. 
***** Receptacle generally without scales. Pappus filiform, 
very soft, deciduous, never feathery nor dilated at the base, 
silvery. 
45. Lactuca. Heads few-flowered. Involucre imbricated in 
2 — 4 rows, outer row shorter, scales with a membranous 
margin. Fr. ])lano-com[)resscd, contracted and produced 
into a Aliform beak which is not crowned nor mm-icated at 
the base. 
46. Taraxacum. Heads many-flowered. Involucre double-, 
inner of 1 row, erect ; outer of few short lax or adpressed 
imbricated scales. Fr. suljcompressed, muricated and sud- 
denly contracted above, produced into a Aliform beak. 
47. Crepis. Heads many-flowered. Involucre double, inner 
of 1 row, outer of short lax scales. Fr. terete, narrowed 
upwards or beaked. 
48. SoNCHUS. Heads many-flowered. Involucre imbricated 
with 2 or 3 rows of unequal scales. Fr. piano-compressed, 
truncate above not beaked. 
49. Mulgedium. Heads many-flowered. Involucre double, 
inner of 1 row, outer of short lax imbricated scales. Fr. com- 
pressed constricted above and terminating in a ciliated disk. 
Outer rows of the pappus rigid and brittle. 
****** Pappus rigid, brittle, at length brownish or yellowish. 
Otherwise like the preceding section. 
50. IIiERACiUM. Heads many-flowered. Involucre imbri- 
cated with many oblong scales. Fr. terete, angular, fur- 
rowed, truncate above not beaked, with a very short cre- 
nulated margin. 
Anomalous Genus. Order AmbrosiacejE Link. 
51. Xanthium. Heads monoecious. Male. Involucre of 1 
row of free scales, many-flowered. Recejrtacle scaly. Cor. 
funnelsba])ed, 5-cleft. Anth. free. Stigma obtuse, entire. — 
Fern. fl. 2, inclosed within the involucre which is terminated 
by 1 — 2 beaks and covered with hooked s])ines and at length 
hardened over the fruit. Cor. Aliform. Stam. 0. Stigmas 
2, diverging, linear. Fr. compressed each occupying a cell 
in the involucre. 
