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HARDWICKE'S SCIENCE-GOSSIP. 



But what shall I say of the Silurian fauna ? Time 

 will not permit me to speak in detail, even if details 

 would interest you, of the small elliptical Lingula 

 minimus, which shines with a dark metallic lustre on 

 the brown Llandovery sandstones of the Obelisk 

 Hill ; nor of its near but more important looking 

 relation, the pearly enamelled L. Lewisii of the 

 Ayme3try. The Atrypa, Discina, Meristella, the 

 Pentamerus, Retzia, and Rhynchonella, and the 

 Spirifera and Strophomena, are all so common in the 

 Wenlock and Ludlow rocks that they may be counted 

 by the hundred. These all belong to the prevailing 

 type of shell of those early periods, the Brachiopoda, 

 which by many hundreds to one outnumber the true 

 molluscan type. A most important group was the 

 Cephalopoda — the chambered type of shell — whose 

 modern representatives are free swimming and 

 carnivorous, and, says Sir R. Murchison, " we may 

 presume that they were the appointed tyrants and 

 chief scavengers of the Silurian seas." Commonest 

 amongst these are the Orthoceras and Phragmoceros, 

 types almost exclusively paleozoic, and the precursors 

 of the Ammonite and Belemnite of Mesozoic times, 

 and of the octopus or devil-fish of modern seas. 

 The Gasteropoda formed an intermediate class, 

 being inferior to the Brachiopoda in regard to 

 numerical strength, and to the Cephalopoda in 

 structural importance. They were the precursors of 

 the modern snail and slug, and the Euomphalus and 

 Murchisonia are the commonest fossils of this class. 

 The Encrinites of Silurian times, represented in 

 these cases by the graceful forms from Dudley, were 

 attached by jointed stems to the rocks, and Hugh 

 Miller, whose graphic powers seem to make obsolete 

 forms instinct with life, says that they " rose in 

 miniature forests, and spread forth their sentient 

 petals by millions and tens of millions amid the 

 waters, while vast ridges of coral, peopled by their 

 innumerable builders — numbers without number — 

 rose high amid the shallows." The earliest remains 

 of fishes in the lowest zone of the Ludlow rocks are 

 very meagre, but in the upper zone remains are 

 found in great profusion. Sir Roderick Murchison 

 says that there is a band or layer of the thickness of 

 three or four inches which exhibited a mass of bony 

 fragments. Some of the fragments of fish are of a 

 mahogany hue, but others are so brilliant a black 

 that, when first discovered, they conveyed the 

 impression that the bed was a heap of broken beetles. 

 I hope the club will search for this bed. 



The passage beds lying in unbroken sequence 

 between the crest of the Upper Ludlow on the east 

 and the base of the Old Red Sandstone on the west, 

 may be well seen at the Ledbury Railway Station, 

 and those of our members who were fortunate enough 

 to hear Mr. Piper, F.G.S., at a recent meeting of 

 the Woolhope Field Club, describing the various 

 beds which he had mapped out and numbered, will 

 Dot readily forget the enthusiasm with which he 



described his capture of the bony plated little ganoid 

 Auchenaspis, and the no less interesting but more 

 common bucklerhead, Cephalaspis. Mr. Piper, with 

 the assistance of Henry Brooks, of local Auchenaspis 

 fame, had commenced his measurements from an Old 

 Red Rock opposite the goods shed, and had found 

 the passage beds, twenty-two in number, to be 400 feet 

 thick, of which about 25 feet only were fossiliferous. 

 Higher up in the Old Red rocks themselves fishes be- 

 come much more common, but although we are within 

 an hour's ride by rail of that interesting and quaint 

 old town of Ledbury, which nestles within an 

 amphitheatre of wood-crowned hills — hills which in 

 response to the hard and diligent appeals of the 

 hammer will readily yield up their treasures, not a 

 single specimen has apparently ever found its way 

 into our Museum. Hugh Miller grows eloquent 

 when contemplating these ichthyic remains. " Some 

 of the fish," he says, "were furnished with bony 

 palates, and squat firmly based teeth, well adapted 

 for crushing the stone-cased zoophytes and shells of 

 the period ; some with teeth that, like those of the 

 fossil sharks of later formations, resemble lines of 

 miniature pyramids, larger and smaller alternating 

 some with teeth sharp, thin, and so deeply serrated, 

 that every individual tooth resembles a row Ol 

 poniards set upright against the walls of an armoury ; 

 and these last, says Agassiz, furnished with weapons 

 so murderous, must have been the pirates of the 

 period. Some had their fins guarded with long 

 spines, hooked like the beak of an eagle ; some with 

 spines of straighter and more slender form, and 

 ribbed and furrowed longitudinally like columns j 

 some were shielded by an armour of bony points ; 

 and some thickly covered with glistening scales." 



But in the formation above the Old Red, the 

 Carboniferous, the fishes, although common, do not 

 so preponderate as to give a special character to the 

 rocks. Land plants become the characteristic fossil, 

 and must have abounded in glorious and luxuriant 

 profusion in those times. In the forest of Wyre Coal 

 Field it is no uncommon occurrence, I am told, for 

 the colliers to find in the "clunch," or stiff red clay 

 which occurs both above and below the coal, the 

 graceful fronds of an ancient fern, showing all the 

 delicate tracery of its venation ; its jet black lustre 

 presenting a striking contrast to the rich red colour 

 of the clay in which it is preserved. Unfortunately, 

 the clay when dry becomes friable, and it is impossible 

 to preserve a specimen in a cabinet for a very long 

 period. It is more like playing at colliers than real 

 work on the margin of the coal-field at Frith Common 

 and Mamble where the pits are only from fifteen to 

 twenty feet deep, and into which we are lowered in a 

 bucket by a windlass. It causes a strange and curious 

 sensation to find ourselves grubbing along on hands 

 and knees in those narrow and shallow workings, 

 lighted up here and there by a naked candle, 

 the end of which is embedded in a lump of soft 



