94 
SILURIA. 
[Chap. V. 
Malvern Wells, on the line of the Worcester and Hereford Railway, that 
the nucleus of the hills there, as at the White-leaved Oak, consists of 
igneous rocks, traversing the old syenitic gneiss, and really constituting 
the centre of the Malvern range. The eruptive rock, however, must have 
cooled and hardened long before the period of the deposition of the Upper 
Llandovery sandstone ; for Mr. Symonds mentions that he was astonished 
to find almost in the centre of the hill two thin bands of that rock, con- 
taining characteristic fossils, which had evidently been deposited in a 
fissure in the syenitic rock when the ridge of the Malverns was submerged 
beneath the sea of the Upper Llandovery period. (Quart. Journ. Geol. 
Soc. May 1861.) 
The lowest of the unaltered deposits which have been termed Silurian 
by Professor Phillips and myself is the Hollybush Conglomerate and Sand- 
stone ; and these are overlain by certain schists, which are in parts so black 
as to have given the name of Coal Hill to some hilly arable ground to the 
west of Keys End Hill (see p. 95). 
These lower strata of sandstone and black shale extend from north to 
south along the slopes of Midsummer Hill, Ragged-stone Hill, and Keys 
End Hill, or the southern portion of the chain, for a length of upwards 
of two miles, and have an average width of half a mile from east to west, 
in which space they are perforated, here and there, by small bosses and 
dykes of intruded greenstone, as laid down in the Map of the Survey*. 
Yolcanic grits and lavas interstratified with both the Hollybush Sandstone 
and Black Shales have been carefully described by Dr. Holl. 
The Hollybush Sandstone is well displayed in quarries at the 114th mile- 
stone on the London-road from Tewkesbury to Ledbury, where the beds 
dip away from the part of the ridge called Ragged-stone Hill at an angle 
of 35°. This Hollybush Sandstone, of a light-greenish tint, containing a 
small portion Of mica, and freckled with a few dark stains, had afforded 
no organic remains, save Eucoids, when the last edition of this work ap- 
peared ; but since then Dr. Grindrod has discovered in it tubes of Sea- 
worms, the Trachyderma antiquissimum of Salter, and some other fossils 
have been found in it by Dr. Holl and Mr. Turner of Pauntley (see p. 45). 
The beds above the conglomerate are thick, but become flag-like upwards, 
and pass through sandy shale into overlying black shivery schists. 
These schists were first described in the 'Silurian System' (p. 416) as pos- 
sibly belonging to the Llandeilo group, — that suggestion having been made, 
in the absence of any known organic remains, from the strata being sur- 
mounted by a zone of sandstone with Pentameri, then believed to belong to 
Caradoc sandstone, followed by a full Upper Silurian series. Subsequently 
Professor Phillips discovered in these schists the small Trilobite Olenus 
humilis ; and afterwards my lamented friend Mr. Hugh Strickland de- 
tected the minute Agnostus pisiformis. The occurrence of these forms, 
* These protuberances of greenstone were first noticed by Professor Phillips. 
