LXII. COMPOSIT X. 531 
26. PTERIGERON, DC. 
(Streptoglossa, Steetz; Oliganthemum, F. Muell.) 
Involucre hemispherical or ovoid, the bracts imbricate in several rows, 
usually dry and rigid or the outer ones herbaceous, the innermost narrow, 
acute, often coloured at the tips. Receptacle without scales. Florets of the 
circumference numerous or few, female, ligulate or, if tubular, less regularly 
omore deeply lobed than those of the disk; disk-florets numerous or few, 
hermaphrodite, fertile or sterile, usually 5-lobed. Anthers with fine tails, 
silky-hairy. Pappus of scabrous denticulate or almost plumose capillary 
bristles. Herbes, usually rigid and glandular-pubescent or hirsute. Leaves 
alternate, entire or toothed, someti decurren 
small, terminal, and usually forming terminal leafy cory 
The genus is exclusively Australian. Originally established by De Candolle as a section 
of Erigeron, it has been shown by A. Gray to form a very distinct genus, allied in many 
respects to Pluchea, but differing in the prominently bulbous base of the style, and usually 
in the irregularity of the ray-florets, which connect it with Dicoma, amongst Mufisiacee. 
c; perhaps to include Coleocoma and Thespidium, notwithstanding their anomalous 
Flower-heads large, almost hemispherical. 
Ray-florets ligulate, exceeding the involuere. 
Leaves ovate, deeurrent.  Ray-florets not 4 line broad . . 1. P. decurrens. 
ves narrow or obovate, not decurrent. Ray-florets fully $ piu" 
BEEN. E undue een A E haroa. 
.. Ray-florets very slender, about as long as the involucre. Leaves 
bou E ae 
oblong, stem-clasping or slightly decurren 4. P. macrocephalus. 
er-heads ovoid. : 
ves decurrent. Ray-florets about as long as the involucre . 3. P. odorus. 
Leaves not decurrent. Ray-florets very slender and shorter 
than the involucre. ; 
Leaves mostly oblong. Flower-heads broadly ovoid, 6 to 8 
a LE i "quen Jm Ja Se 
ves mostly linear. Flower-heads numerous, many-flowered, 
about 4 itis lohg 6020-49 Le vt A ok Uy s 6. P. adscendens. 
Leaves filiform. Flower-heads narrow, 8- or 4-flowered, 
Bout © his SE EE 
5. P. microglossus. 
T. P. filifolius. 
. l. P. decurrens, DC. Prod. v. 293 (as an Erigeron). A rigid branch- 
ing herb, glandular-pubescent and hirsute. Leaves ovate or oblong, coarsely 
volucre ovoid when young, nearly hemispherical and j in. diameter when 
filly out, the outer bite herbaceous, surrounded by a few floral leaves, the 
