244 PITTONIA. 
The worthiness of Cesalpinus to be ranked among the 
most illustrious of botanists is best attested by the fact that 
he published a beautiful book—setting forth new principles, 
and full of new deductions—which the botanical world was 
not ready to adopt until a hundred years afterwards; and 
his new genera had to wait from the year 1583 until 1694 
before meeting with acceptance. 
Tournefort’s Elemens, though scarcely more than an 
enlarged and illustrated edition of Cesalpinus’ modestly- 
entitled volume De Plantis of a hundred and eleven years 
before, converted the world almost at once to the true prin- 
ciples of plant classification, and, in itssecond edition, Insti- 
_tutiones Rei Herbariz, became the one great landmark in 
the history of botanical science. There has never been 
another book to equal it in its influence for the advancement 
of systematic botany; nor does it seem possible that its equal 
as an epoch making treatise can arise in the future. 
In both the Elemens and the Institutiones of Tournefort 
Bidens of Cesalpinus is given its place. The number of 
species included in it by this author is thirteen. Two of 
them are Cesalpinus’ original ones. Five are transferred 
hither from other nominal genera, and six are proposed as 
new. But the Bidens of Tournefort embraces a number of 
species not naturally of this genus; the type species, for 
example, of Verbesina and of Actinomeris, both being tech- 
nically at agreement with Bidens as to the external char- 
acters of a flattened achene and a biaristate pappus. 
Vaillant, in 1720, revising the genus under the new and 
needless name of Ceratocephalus, excludes the Actinomeris 
and Verbesina, and still has twenty species, among which 
we recognize a part of the material upon which Coreopsis 
was afterwards to be established. 
Dillenius, a dozen years later, restored the name Bidens’ 
