Notes and Comments. 355 
The plant was originally compared with the so-called H. 
cylindricum, but is at least as close to H. tiliwoides. The 
‘ feature which at first seemed to be most striking is the fact 
that four distinct leaf-trace bundles enter the base of the leaf, 
each of them dividing into two in the petiole. This is certainly 
the best example yet found of a polydesmic petiole in Heter- 
angium, and shows an interesting approach to the Medullosez 
in this respect. We may also compare Dr. Gordon’s new genus 
Rhetinangium. 
POLYDESMIC HETERANGIUM. 
However, there is reason to believe that most of the British 
Coal Measure Heterangiums were polydesmic. In H. tiliwoides 
there are four distinct bundles in the petiole, and the same was 
the casein H. Lomaxit. In all these plants two bundles start 
from the stele to form the leaf-trace, dividing into four, at 
least in some cases, before entering the leaf-base. Only in a 
very small stem from Dulesgate (not associated with JH. 
Lomaxit) did a single bundle leave the stele (as in the Burnt- 
island species) dividing into two on its outward course. This 
little stem has nothing to connect it with any other form and 
may be distinguished as H. minimum.  H. tilicwotdes is main- 
tained as a distinct species, mainly on the ground of its highly 
developed phloem with dilated medullary rays. In the be- 
haviour of the leaf-traces it comes very near the Shore plant, 
which may, for the present at least, be kept distinct under the 
name H. shorense. 
FOSSIL FUNGI AND FOSSIL BACTERIA. 
Dr. D. Ellis reported that an investigation of the ferruginous 
and fossiliferous rocks of Great Britain showed that some of the 
organic fragments in the ferruginous rocks had been in a state 
of putrefaction when engulfed. A study was made of the 
micro-organisms which were responsible for this putrefaction. 
A fossil fungus was found in the Frodingham Ironstone of 
Lincolnshire (Lower Lias). To this organism the name Phy- 
comycites Frodinghami has been given. Characteristics.— 
Hyphe of two dimensions, namely 2 » and 34 p respectively. 
The two sizes of hyphe were found in organic connection. 
There were no traces of transverse walls. In addition to the 
ordinary alternate branching whorls of hyphe arising from 
the same level were frequently observed. In many places 
the threads showed thickening cushions. Some of these were 
apparently in‘association with the formation of branches and 
were of a supporting nature ; others, however, had no apparent 
significance. Some of the hyphe had terminal dilatations of a 
sporangial nature, as in a few cases spore-like bodies were 
enclosed in them. The sporangia measured about 24 p (4, mm.) 
and were roughly spherical. The spores were Io » in diameter. 
1915 Noy. 1. 
