22 ; BOTANICAL GAZETTE [JULY 
Bidens leucantha (L.) Willd. or B. pilosa L.; but in tall, slender habit, nature 
of pubescence, and short, See exaristate character of fruit they are very 
distinct from either of these species 
Bidens cornuta, sp. nov.—Herba annua, 3-5 dm. alta; caule 
et ramis tetragonis, striatis, glabris, tenuibus. Folia opposita, 
petiolata, petiolo adjecto 3-12 cm. longa, 3-6 cm. lata, pinnata 
(aut summa bipinnata), ciliata, supra subglabra, infra sparsim 
adpresso-hispida; foliolis vel dentatis vel incisis vel etiam (imis 
foliorum superiorum): distincte partitis, ovatis aut lanceolatis; 
petiolis o.3—3 cm. longis, glabris, ad basim hispidam connatis. 
Capitula terminalia, discoidea (aut interdum subligulata ?), tenuiter 
pedunculata pedunculis 2-9 cm. longis. Involucrum basi glabrum, 
squamis duplici serie dispositis; exterioribus (5-8) linearibus, 
glabris aut infra hispido-ciliatis, 2-3 mm. longis; interioribus late 
linearibus, glabris, striatis, margine diaphanis, 4-5 mm. longis. 
Paleae lineares, striatae, margine diaphanae, demum 5-10 mm. 
longae. A anguste linearia, striata, triaristata; maturis 
aristis longis (5-7 mm.) et divaricatis, supra tenuissime et retror- 
- achaeniorum subbadiis, hispidis, 6-10 mm. longis; interioribus 
elongato-attenuatis, nigris vel subnigris vel ad ae mica 
infra glabris, supra hispidis, 4.3-2 cm. longis. _ ae : 
. Dr. Edward Palmer 131, at altitude of 730 m., Hacienda San Miguel 
cue : : Chihuahua, Mexico, August, ee 5 (typ ae erb. Gray). 
= Asa Grav had treated this plant as “Bidens ose eal aristis 
_demum patentissimis” ; but from B. bipinnata it differs decidedly in its less 
_ divided foliage, its narrower, more elongated, fewer-fruited heads, and its 
peculiar | achenes with awns i still aceon) —* that, especially 
ov . E deade tees Oc ed ee oo. 
Y ceciencunen 
Poncseigee sap ot  f 
