Bidens. | COMPOSITAE. 99]. 
Achene broad and compressed or slender and tetragonous, often narrowed 
at the tip. Pappus of 2-4 rigid retrorsely hispid bristles. 
A large genus of over 109 species, widely spread in tropical regions, but most 
plentiful in America. The single New Zealand species is a common weed in all warm 
countries and many temperate ones. 
Encree 1. B. pilosa Linn. Sp. Plant. (1753) 832. —An erect glabrous or pubes- 
variable, 
us ? rT ovate- 
Bidens pilosa, Linn. d mem- 
> 3.9 LE 
a i a Le € Le are rt, often 
not native to N.: se . tetas 
GF ; . Precur. 
vol. 57, pe 62 (Ckn. & Allan). I. (1864) 
99) 318 ; 
Weer, ane wive 427 wove \huuyuy Yaie. ay. AULaIvAaALUD WU. til Lrals, N:Z. 
Inst. xxvii (1895) 388. 
KeERMADEC IstANDs, NortH Istanp; Not uncommon as far south as the East 
Cape. Novem ber—March. 
19. COTULA/Tourn.) L. (97S 
Creeping or tufted perennial or annual herbs, usually of small size, often 
aromatic. Leaves alternate, pinnatifid or pinnatisect, rarely entire or 
toothed. Heads small, peduncled, heterogamous and discoid or rarely 
homogamous through the suppression of the female florets, sometimes 
dioecious. Involucre hemispheric or campanulate; bracts in about 2 
series, membranous or herbaceous; margins often scarious. Receptacle 
flat or convex or conical, without scales. Female florets exterior, in 1 or 
2 series, fertile; corclla broad or conic or wanting. Disc-florets herma- 
phrodite or often male; corolla regular, tube slender or stout and 2-winged, 
limb 4-toothed. Anthers obtuse at the base, entire. Style-branches of the 
disc-florets truncate or obtuse, sometimes undivided. Achenes compressed, 
sometimes winged. Pappus wanting. 
A genus of-50 or 60 species, scattered widely over the world in both temperate and 
tropical regions. Several of the New Zealand species are difficult of discrimination, 
and require further study with more copious suites of specimens. 
A. Eucotula. Receptacle flat or conver. Female florets without any corolla. Achenes 
of the female florets stipitate, in a single row. 
Stout, glabrous, 2-10 in. high. Leaves STOLE, 4-2 in., vari- z 
ously - toothed or lobed. Heads yellow, 4-4 in. diam. .. LL. C.coronopifolia. « 
B, Strongylosperma. Receptacle flat or convex. Female florets without any corolla. 
Achenes of the female florets in several rows. 
Slender, diffuse, silky. Leaves pinnate or bipinnate. Heads 
small, 4,4 in. diam. 
ho 
. C, australis. 
C. Leptinella. Receptacle convex or conical. Female florets in I or several series ; 
corolla always present, usually injlated at the base. ‘ 
* Heads bisexual. 
Stout, fleshy. Leaves }-lin., much divided. Peduncles leafy. 
Heads black or dark: brown, Florets tubular or cylindric; 
rugose .. 93 C. atrata. 4 
Sh softly woolly. ifewees 2-611 in., 3-4- Spinnatisens Heads 
yin. diam. ; florets eglandular .. aa bse -- + C. plumosa, 
