Reprinted from the Botanical Gazette, 59: No. 4, April 1015 



STUDIES IN THE GENUS BIDENS. II 

 CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY 201 



Earl E. Sherff 



(with three figures) 

 Bidens acuticaulis, sp. nov.— Herba annua, tenerrima, 4-8 dm. 



alta; caule acute angulato, ramoso; ramis adscendentibus, acute 

 angulatis et fere subalata, remote pubescentibus. Folia opposita, 

 petiolata, petiolo adjecto 1-4 cm. longa, pinnata aut irregulanter 

 bipinnata; foliolis (et lobis) linearibus, o. 5-1 mm. latis. Petioli 2-10 

 mm. longi. Capitula multa, terminalia, 3-4 mm. alta et 2.5-3.5 

 mm. lata (frutescentia demum 1-1.2 cm. alta et 4-5 mm. lata), 

 ligulata. Involucrum basi pubescens; squamis duplici serie dis- 

 poses; exterioribus linearibus, plus minusve pubescentibus, 3-4 

 mm. longis; interioribus lanceolatis, marginibus diaphanis 1.5-3 

 mm longis. Ligulae circiter 4, parvae, sub-flavidae aut fere albae, 

 2- (4-) striatae, 3-5 mm. longae. Paleae lineare-lanceolatae, 

 striatae, marginibus diaphanis. Achaenia linearia, remotissime 

 pubescentia, margine adscendente-ciliato, apice erecto-hispido 

 et biaristato aristis retrorsum hamosis, 6-12 mm. longa. 



John Gospeller 4052, in herb-grown woods, Angola, April 4, 1906 (type 

 in Herb. Brit. Mus.). 



Bidens rufovenosa, sp. nov.— Herba erecta, perennis (?), 4-6 

 dm. alta; caule subtereto, striate, glabro, plus minusve ramoso; 

 ramis (aut ramulis) monocephalicis. Folia opposita, petiolata, 

 petiolo adjecto 4-6 cm. longa, pinnata, spinuloso-ciliata, supra 

 sparsim et brevissime spinuloso-pubescentia, infra sparsim pubes- 

 centia et ad venas minute rufo-tomentosa; 1 foliolis lateralibus 

 lanceolatis (aut foliorum superorum Lineare-lanceolatis) , incisis 

 aut longe dentatis; foliis supremis integris et lanceolatis, aut ter- 

 natis, foliolis integris et lanceolatis; petiolis basi connatis, foliorum 



' Dr S Eckerson, of the University of Chicago, has kindly made for me a critical 

 examination of a leaf from the type, and she reports the color of the pubescence due 

 to a red stain produced in the mucilage cells along the veins. 



, [Botanical Gazette, vol. 59 



