Hornea Lignieri Kidston & Lang. |.c. p. 616. 
**Plant small, consisting of a lobed rhizome trom 
which arise stems which branch dichotomously and range 
from 2 mm. in diameter downwards. Stele of stem with 
a zone of phloem surrounding the xylem composed of 
small central and wider peripheral tracheides. Sporangia 
cylindrical, terminal on branches, indehiscent, with thick 
wall composed of thickened epidermis, thin-walled tis- 
sue, and persistent tapetal layer. Sterile columella com- 
posed of thin-walled elongated cells extending from base 
to near top of sporangium. Homosporous. Spores about 
50 pw. in diameter.’ 
Locality— Muir of Rhynie, Aberdeenshire, Scotland. 
Horizon—Old Red Sandstone, Middle Devonian. 
There are no synonyms for this monotypic genus. 
The fossil plant is a member of the Rhyniaceae, in the 
order Psilophytales. 
Inasmuch as the fossil ‘‘Hornea’’ is both better 
known and of much greater importance to the botanist 
and paleobotanist than the sapindaceous genus of the 
same name, it is unfortunate that a duplication of names 
has occurred. However, we propose to change the name 
of the Devonian psilophyte, hitherto known as Hornea 
Ligniert to Horneophyton Lignieri. This new name 
reduces possible confusion to a minimum. The root 
Horneo involves but slight orthographic change, and the 
sufhix phyton is very frequently used in the naming of ex- 
tinct plants—particularly those found in rocks of Devo- 
nian age, 
Horneophyton rom. nov. 
Hornea Kidston & Lang, non Baker. 
Horneophyton Lignieri ( Kidst. & Lang) comb. 
nov. 
Hornea Ligniert Kidston & Lang. 
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