Blake — A Revision of the Genus Viguiera 177 
angustissime linearibus valde revolutis, involucri 3-5-seriati 
gradati phyllariis lanceolatis vel lineari-lanceolatis acuminatis 
infra valde costatis vittatis et plus minusve induratis supra her- 
baceis. — Species typica V. filifolia Sch. Bip. — Erect virgate 
herbaceous perennials, with very leafy simple stems and linear or 
linear-filiform leaves, of Paraguay and adjacent Brazil. 
a. Involucre 1-1.5 cm. high; leaves 1-3 mm. Va AL. 
Leaves 2-3 mm. wide; involucre 5-seriate ......... 133. V. densifolia. 
b. Leaves 1-1.5 mm. wide; involucre 3—4-seriate, c. : 
c. Phyllaries densely canescent-strigillose between mid- 

erve and MAMIN . oo. Len ein yee oe 132. V. filifolia. 
Phyllaries green, sparsely strigillose ........... 134. V. linearifolia. 
a. Involucre 7-9 mm. high; leaves 0.4-0.8 mm. wide, d. ; 
aves 5.5-7 cm. long, 0.8 mm. wide ..............- 135. V. Rojasii. 
d. Leaves 7-12 cm. long, 0.4-5 mm. wide .......... 136. V. trichophylla. 
132. V. ritiroL1a Sch. Bip. “ Perennial herb, 0.6-1 m. high,” 
simple or (abnormally) branched near the middle, the branches 
erect. Stem very slender, leafy (the leaves mostly 6-9 mm. apart), 
rather sparsely tuberculate-strigillose. Leaves linear-filiform, 
faleate-recurved, callous-mucronate, strongly revolute, above 
green, densely lepidote-tuberculate-strigillose, the midnerve pale 
and rather prominent, beneath whitened with a dense cottony 
tomentum between the costa and margin, the lower 8.5-19 cm. 
long, 1-1.5 mm. wide, the upper gradually smaller, the uppermost 
bractlike and grading into the involucre. Heads 1-21 or more, on 
erect leafy pedicels, subumbellately cymose-panicled, about 2.5 em. 
broad; disk 1.1 em. high, 1.5 cm. wide. Involucre 3-4-seriate, 
considerably exceeding disk, the phyllaries with ovate or lanceolate 
body (1-nerved, tuberculate-strigillose on the nerve, densely 
canescent-strigillose between midnerve and margin) and attenuate 
to an ascending loose or at length reflexed more herbaceous tip. 
Rays (about 12 ?) narrowly oblong, 8 mm. long; disk-corollas sub- 
glabrous, 5 mm. long (tube 1 mm.). Pales firm, narrow, striate, 
slightly keeled, abruptly narrowed into a firm slightly recurved 
cusp (1.5 mm. long), puberulent above, 8 mm. long. Achenes 4- 
angular, subglabrous, 3 mm. long. Awns linear-lanceolate, 1- 
1.5 mm. long; squamellae about 3 pairs, subequal, lacerate, more 
or less united below, 0.7 mm. long; whole pappus sometimes 
purple-tinged. — Sch. Bip. ! ex Baker in Mart. Fl. Bras. vi. pt. 3. 
219 (1884). BRAZIL: grassy mountain fields near Cinza and 
on the shores of the Rio Pardo, Riedel (rvPe cou.: G., K.). 
