16 RypBerG: STUDIES ON THE Rocky MOUNTAIN FLORA 
combining characters of both. Either the two genera should be 
united or else this species and several others of the southwestern 
United States and Mexico should be separated as a distinct genus. 
Even Fries in his Symbolae Hieraciorum recognized this fact 
and suggested the:name Crepidispermum. He did not exactly 
publish the genus and no binomial names were given under the 
genus. Besides, in the same year a genus Crepidospermum B. & H. 
was published. The two names differ only in one letter, the 
connecting vowel 7 in one case and o in the other. The former is 
the Latin connecting vowel, the latter the Greek, which is some- 
times used in Latin for euphony’s sake. The two names may 
therefore be regarded as identical. The two brothers Schultz of 
Zweibruecken adopted Fries’ suggestion and established the 
genus under the name Heteropleura, as alternate ribs of the 
achenes are stronger. The present species was given the name 
Heteropleura ambigua, based on Crepis ambigua A.Gray. As there 
is an older C. ambigua Balb., that specific name is not available, 
and hence I have adopted Heteropleura Fendleri. 
AGOSERIS 
Professor Nelson reéstablishes the name Troximon for this 
genus, evidently following as he thought the Vienna Rules and 
cites Nuttall as authority for the genus. This is a similar case 
to that of Actinella and Tetraneuris. In fact Nuttall never estab- 
lished a genus Troximon. He thought that his two species be- 
longed to the genus Troximon Gaert. Troximon of Gaertner 
was established in 1791 on Tragopogon Dandelion, T. virginicum, 
and T. lanatum, of which the first two belong to one genus, Krigia 
or Adopogon, and the last is a Scorzonera. Even if Nuttall had 
established a genus Troximon, this would not hold, for then it 
was not published before 1818 in his Genera, while Rafinesque’s 
name dates from 1817. It is true that Troximon appeared in 
Fraser’s Catalogue of 1813, but there it is without description. 
In his Genera, Nuttall credits Gaertner with the name. So does 
also Pursh in his Flora, 1814. There is therefore no warrant for 
reviving Troximon for the genus known in later years as A goseris. 
A good deal may be said regarding Professor Nelson’s treat- 
ment of this genus, especially in the way synonyms have been 
