i 9 2o] SHERFF—BIDENS 1 09 



Bidens linearifolia (O.andH.), comb, nov. — Coreo psis linearifolia 

 Oliver and Hiern, Fl. Afr. Trop. 3:390. 1877; Bidens Schweinfurthii 

 SherfT, Bot. Gaz. 59:309. 1915. — In 1915, on finding it necessary 

 to " transfer this species from Coreopsis to Bidens, I purposely 

 created the new name Bidens Schweinfurthii "to avoid any possible 

 confusion with Bidens linearifolia Schz. Bip." (Bot. Gaz. 59:309). 

 This appeared to me to be much the most desirable procedure. 

 Nevertheless, in view of the fact that Bidens linearifolia Schz. Bip. 

 is not a true Bidens, but is rather a species of Cosmos (C. linearifolius 

 Hemsley, Biol. Centr. Amer. 2:200. 1881), the International Rules 

 require the retention of Oliver and Hiern's trivial name. 



University of Chicago 



EXPLANATION OF PLATES XI-XIV 



PLATE XI 



Bidens exigua (a-f) and B. duranginensis (g-m 1 ): a, an entire plant 

 X0.64; a', fruiting head X 0.64; b, b', exterior involucral bracts Xs; c, interior 

 involucral bract X5; d, palea X5; e, disk floret X5; /, /', outer and inner 

 achenes Xs; g, branch and portion of main stem X0.64; h, exterior involucral 

 bract X5; i, interior involucral bract X5; j, ligulate floret Xs; k, palea Xs; 

 I, disk floret X 5 ; m, m', outer and inner achenes X 5 ; a-f, from type of B. exigua 

 in U.S. Nat. Herb. ; g-m', from type of B. duranginensis in Herb. Gray. 



PLATE XII 



Bidens asplcnioides (a-f) and B. Stokesii (g-o): a, branch X0.61; b, 

 exterior involucral bract X6; c, interior involucral bract X6; d, ovary X6; 

 e and/, fragments of mature achenes X6; g-i, branch and additional leaves 

 X0.61; j, exterior involucral bract X6; k, interior involucral bract X6; 

 /, ligulate floret X6; m, palea X6; n, disk floret X6; 0, achene X6; a-f, 

 from type of B. asplcnioides, g-o, from type of B. Stokesii, both in Herb. Bishop 

 Mus. 



PLATE XIII 



Bidens gracilis (a-i) and B. cuneata (j-p) : a, branch Xo . 7 1 ; b, leaf Xo . 7 1 ; 

 c, exterior involucral bract X7; d, interior involucral bract X7; e, ligulate 

 floret X7; /, palea X7; g, disk floret X7; h and i, achenes X7; j, branch 

 and two old peduncles, apparently of previous season's growth X0.71; k, 

 exterior involucral bract X5; /, interior involucral bract X5; m, ligulate 

 floret Xs; n, palea X5; 0, disk floret X5; p, achene Xs; a, c-i, from Mann 

 and Brigham 98, Herb. Bishop Mus.; b, illustrating trifoliate leaf, from Forbes 

 1 184 O. Herb. Bishop Mus.; j-p, from type of B. cuneata, Herb. Bishop Mus. 



PLATE XIV 



Bidens Forbesii: a, upper portion of plant X0.61; b, leaf from sterile 

 branch X0.61; c, exterior involucral bract X6; d, interior involucral bract 

 X6; e, ligulate floret X6; /, palea X6; g, disk floret X6; h, very young 

 achene X6; i, mature achene X6; a, c-i, from first type sheet, b, from second 

 type sheet in Herb. Bishop Mus. 



