468 CocKERELL: NortTH AMERICAN SPECIES OF HYMENOXYS 
' 
will be granted that the matter is not so simple as here pictured ; 
but I think that the facts warrant the suggestion made, admitting 
various minor qualifications. 
Notwithstanding the evident plasticity of the species, they are 
more nicely adjusted to their surroundings by true racial characters 
than one would at first suspect. Thus A. Vaseyi appears to 
remain in the Organ Mountains, although the rains must often 
wash its seeds down to the adjacent lowlands. A. floribunda utilis © 
insists upon occupying quite high altitudes in central Colorado, 
although other floribunda forms (in New Mexico and Arizona) give 
it a precedent for going lower ; and what is perhaps more curious, it 
has not appeared at all on the east side of the front range. Then 
again, 17. floribunda utilis ceases abruptly in central Colorado, and 
going a little north we find abruptly beginning and very abundant 
the large-headed H. Richardsoni macrantha. Now it is difficult 
on the face of things to say why macrantha should not be common * 
as far south as Santa Fé, and floribunda as far north as Wyoming. 
’ Hymenoxys Richardsoni (Hooker) 
Picradenia Richardsoni Hooker, Flora Boreali Americana, I: 
317. pi 1 08. 1633. 
Actinella Richardsonii Nuttall, Trans. Amer. Phil. Soc. 7: 379: 
1841. 
I am greatly indebted to Mr. O. F. Cook for a copy of the 
original description and a photograph of the plate. The description 
is as follows: 
a Radix subfusiformis, lignosa, descendens, ramosa, superne 
divisa. Caules subspithamaei, erecti, rigidi, glabri, striati, superne 
ramosi. folia 3-4 uncias longa, lineari-filiformia, cau/ina pauca ; 
(seu receptaculum) conica, carnosa, punctata, ebracteata. Flosculi 
radit ligulati, obovato-oblongi, lutei, tubo praecipue glandulosi, 
apice dentibus 3 grossis ; disci tubulosi, 5-dentati, flavi, glandulis 
valde amaris tecti. Amtherae subexsertae. Stigmata inclusa, 
breviuscula, apice incrassata et hirsuta. Achenium oblongum, 
