172 
45. COMPOSITE. 
***** Pappus fliform, deciduous, never feather]/ nor dilated at 
the base. Receptacle guierally without scales. Fruit com- 
pressed. 
41. Lactuca. Heads few-flowered. Phyll. with a mem- 
branous margin, imbricate iu 2 — 4 rows ; outer row shorter. 
Fr. plane-compressed, contracted and prolonged into a fili- 
form beak which is not crowned nor muricate. 
42. Leoxtodo?.'. Heads many-flowered. Inv. double i inneT 
phyU. in 1 row, erect ; outer few, short, lax or adpressed, 
imbricate. Fr. subcompressed, muricate and suddenly con- 
tracted above, prolonged into a filiform beak. 
43. SoNCHTJS. Heads many-flowered. Phyll. imbricate in 
2 or 3 rows, unequal. JFV. plane-compressed, truncate, iwt 
beaked. 
44. MrLGEDirM. Heads many-flowered. Inr. double; inner 
phyll. in 1 row ; outer short, lax, imbricate. Fr. compressed, 
constricted above, and ending in a ciliate disk. Outer rows 
of the pappus rigid and brittle. 
****** Fruit terete, ribbed. Other^cise like the preceding section. 
45. Cbepis. Heads many-flowered. Inv. double; inner 
phyU. in 1 row ; outer short, lax. Fr. terete, narrowed 
upwards or beaked. Pappus soft. 
46. HxEBAcriTM. Heads many-flowered. Phyll. imbricate, 
many, oblong. Fr. truncate, not beaked, with a very short 
crenulate margin. Pappus brittle. 
[Anomalous Genus. Order AMBROsiACEiE Link.] 
[47. Xanthium. Heads monoecious. — Male: inv. of 1 row 
of free phyll., many-flowered. Receptacle scaly. Cor. 
funnelshaped, o-cleft. Anth. free. Stigma blunt, entire. 
— Fern. fl. 2, inclosed within the inv. which ends in 1 — 2 
beaks, is covered with hooked spines, and hardens over the 
fruit. Cor. 0. Stam. 0. Stigmas 2, diverging, linear. 
Fr. compressed, each occupying a cell in the involucre.] 
Suborder!. TUBULIFLOHjE. Perfect flowers tubular, 
regular, teeth 4 or 5. 
Tribe I. Eupatoriece. 
Style of the perfect fl. cylindric ; branches long, slightly 
clavate, downiy above. Stigmatic lines slightly prominent, 
often not extending to the middle of the branches. 
