286 Reports & Proceedings—Liverpool Geological Society. 
light. Relics of aerial branches also occur, but these are in a state 
of preservation much less favourable for microscopic study. ‘The 
tissues in the main roots where in the best condition have been 
preserved in calcareous material, which permits the employment of 
high powers of magnification, and the structures are undeformed by 
pressure, but the aerial stems are preserved in iron pyrites, the 
opaque crystals of which have quite obliterated the finer details. 
It would seem that the roots, embedded in the soft mud and readily 
accessible to the petrifying mineral solutions, had thus had their 
harder parts preserved from decay and enabled to resist the pressure 
exerted by the overlying deposits. The aerial branches, on the 
other hand, shaken from the dead trees were already much decayed 
and deformed by pressure before the mineral solutions had the 
opportunity to act. A series of specimens from the locality was 
exhibited, including microscope sections shown by the aid of the 
micro-proj ector. 
I1J.—Liverroot Geronocicat Society. 
April 11, 1916.—J. H. Milton, Esq., F.G.8., F.L.S., President, in 
the Chair. 
The following paper was read :— 
‘‘ Notes on some Ferruginous Nodules in the Panna Triassic Sand- 
stones of South-West Lancashire.” By T. A. Jones. 
The author first described some small hard spheroidal concretions 
found last year during trench digging at Knowsley Park, presumably 
in Lower Soft Bunter Sandstone. They consisted of sand-grains 
embedded in a dark-brown cement of hydrated ferric oxide, which in 
volume was at least equal to the detrital material. The cores of the 
concretions were lighter in colour and less perfectly cemented than 
the outer shell. A striking feature was the large quantity of secondary 
silica present. 
The so-called ‘sulphur-balls’ found in large numbers in colliery 
borings at Wigan and St. Helens in soft sandstone overlying the Coal- 
measures were then described. These consist of well-rounded grains 
of quartz and quartzite cemented by iron pyrites or marcasite. The 
most interesting and significant feature characterizing them is the 
presence of small knots of grains cemented by calcite. Tiny fragments 
of calcite also occur attached to the detrital grains, or le isolated in 
the ferric sulphide. A gradual replacement of an earlier calcareous 
cement by ferric sulphide has therefore taken place, and this without 
disturbing the stratification of the sand-grains which is clearly visible 
across the nodules. A _ brief discussion of the origin of the iron 
cementing material in the sandstones followed. 
CORRESPON DEHN CEH. 
THOUSAND FOOT PLATFORM IN ARRAN. 
Sir,—Dr. F. Mort, in his paper on ‘‘ Glacial Erosion in N. Arran” 
(abstract Trans. Geol. Soc. Glas., vol. xv, p. 415), calls attention to 
a 
