131 
1 917-18. J Phycomycetous Fungi. 
also due to Mr James Lomax for supplying information regarding the 
origin and nature of the slides which have been submitted to examination. 
Peronosporites gracilis (Renault) Ellis. 
Syn. : Palceomyces gracilis (Renault). 
Palceomycites gracilis (Meschinelli). 
B. Renault, Etudes des gttes mineraux de la France : Bassin houiller et 
permien d’Autun et d’Epinac , fasc. iv, “Flora fossile,” Paris, 1896. 
Meschinelli, Fungorum fossitium omnium hucusque cognitorum Icono - 
graphia, 1902. 
This fossil fungus is very widely distributed in the Lower Coal Measures ; 
it was first recorded by Renault, who found it in a Lepidodendroid stem 
from the French Carboniferous Rocks (8). As Renault’s work was not 
available, information concerning the salient features of the organism was 
obtained from Meschinelli’s excellent synopsis (5, p. 9, tab. v, fig. 14 ; tab. 
vi, fig. 1). This writer, having regard to the convention adopted in 
naming fossil genera, has changed the name to Palceomy cites gracilis. 
As is shown below, the affinity to the genus Peronosporites is so close that 
it becomes necessary to incorporate Renault’s organism in that genus. It 
is therefore proposed to rename this species Peronosporites gracilis ; this 
will result in two species being included in the genus Peronosporites, 
namely, P. gracilis and P. antiquarius. The probable close relationship of 
these two fossils has already been commented upon by Seward with 
the remark that " the two fossils should probably be placed in the 
same genus.” 
The best examples of Peronosporites gracilis were obtained from a 
specimen containing a tangential longitudinal section of a stem of Lepi- 
dodendron aculeatum about 2J cms. in diameter. The section had not 
uncovered the stele. The cortex is divisible into two zones — an outer, 
with thick-walled cells ; and an inner, consisting of soft parenchymatous 
cells. The external surface is covered by the crowded bases of the leaves. 
In the basal part of the stem a number of Stigmarian rootlets are shown in 
transverse section. The specimen was derived from the Upper Foot Mine. 
The fossil was also found in another specimen from the same locality, in 
this case a young stem of Lepidodendron Harcourtii of approximately 34 
cms. diameter. Finally, it appeared in a small secondary root of Kaloxylon 
Hookeri (the root of Lyginodendron Oldhamium ) which was found in a 
petrifaction from Dulesgate, near Todmorden. It has already been stated 
that the coal worked at Dulesgate and at Shore belong to the same seam. 
