1917] SHERFF—BIDENS 29 
GREENMAN (Proc. Amer. Acad. 41: 265. 1905), relying upon 
the erostrate achenes, retained ‘‘B. Seemannii” in Bidens.. But, 
as might be inferred already, if this treatment were to be adopted, 
then the subgeneric congeners of this species, such, for example, 
as Cosmos crithmifolius, would likewise have to be placed in Bidens, 
a procedure that surely would meet with little acceptance, if any. 
Thus it seems best to follow the views of Gray and Hemstey in 
this matter and treat the species as Cosmos Seemannii (Schz. 
Bip.) Gray. 
Besides th f C. Seemannii listed by GREENMAN (loc. cit.), [have 
examined the followitig: J. N. Rose 3435, in the Sierra Madre, near Santa 
Teresa, Terr. de Tepic, Mexico, August 11, 1897; Dr. Edward Palmer 1852, 
Tepic, Terr. de Tepic, Mexico, January 5—February 6, 1892; Arséne, Cerro 
San Miguel, Morelia, Mexico, February 1909. 
“BIDENS PaLMERI” Gray, Proc. Amer. Acad. 22: 429. me 
This species, with its strongly ribbed leaves, is very close to 
Cosmos crithmifolius H.B.K., but cats in its oneal rays and 
slightly different leaf outline. In most the achenes 
are clearly erostrate, but occasionally some ‘of gral central achenes 
become highly elongated above, appearing almost distinctly. 
rostrate and thus exactly simulating those of such species as 
Cosmos crithmifolius and C. linearifolius. This is especially no-— 
table in certain material collected by Barnes and Land (nos. 164 — 
and 189, in Herb. Field Mus.). In fact, the subrostrate character ee 
of the achenes was known to Gray (cf. Gray, loc. cit., “ acheniis 
subulatis ... subrostratis ”). Yet, curiously enough, he placed. 
this species in Bidens, while previously (Proc. Amer. Acad. 19: 
10. eS as shown 
: above, to to the Chiact ght 5 it, described = himself as. wigs ae 
