HORNEOPHYTON, A NECESSARY CHANGE 
OF NAME FOR HORNEA 
BY 
Eso S. BARGHOoRN, JR. AND WiLLIAM C, DarRRAH 
In 1920, Robert Kidston and William H. Lang de- 
scribed under the name of Hornea Lignieri a remarka- 
ble fossil plant from the Middle Devonian Rhynie Chert 
of Scotland. Morphologists have regarded this fossil as 
of great phylogenetic significance so that it is very well 
known; indeed it is so well known that it appears in 
elementary textbooks of botany and geology. 
Recently, during the progress of working over a new- 
ly acquired collection of specimens of woods of existing 
angiosperms received by the Biological Laboratories of 
Harvard University, it was discovered that the name 
Hornea had also been used for a sapindaceous tree. Ref- 
erence to the original description of this species showed 
that it belonged to a monotypic genus which had_ been 
described by J. G. Baker in 1877. The prior use of the 
name Hornea in the Sapindaceae thus preocecupies the 
generic designation for the fossil psilophyte, Hornea 
Ligmert. According to the International Rules of Bo- 
tanical Nomenclature, it is necessary to give a new name 
to the fossil plant because of a prior use of the generic 
name Hornea. Interestingly enough, the fossil form is 
much better known and is, by far, more familiar than 
the extant Hornea which occurs in Mauritius. 
The original descriptions of Hornea mauritiana Baker 
and Hornea Ligniert Kidston and Lang are here copied. 
Hornea Baker. 1877. Flora of Mauritius and the 
Seychelles. London. p. 59. 
‘Flowers polygamous. Sepals 5, round, much im- 
bricated, silky on the back, naked on the face, the two 
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