68 



fossils and the position it holds in the series of rocks. It has been deposited here 

 subsequently to very great changes of level, and enormous periods of denudation. 

 This is shown by its almost invariably lying unconformably on a subjacent strata. 

 All the formations which lie west of the Longmynd preceeded it. The Longmynd 

 itself, computed at 26,000 feet thickness of rock ; the Liogula flags, probably 

 1,000 feet ; then the Tremadoc slates, supposed by Professor Ramsay to have a 

 thickness of 6,000 feet in Merionethshire; 'and lastly, the Lower Llandovery 

 rocks. When these had all been deposited, upheaved, and denuded, the Llan- 

 dovery stratum, of which he was speaking, had been thrown down on the sea 

 bottom. The Tremadoc slates is the only stratum in this series which is not 

 shown in the country before them. Portions of the Llandovery rock are found 

 in various parts of this district, occurring in patches, which have resisted the 

 forces to which the whole has been subjected. But the most striking portion is 

 that which clothes, as it were, the slopes of the Longmynd, dipping away from 

 that mountain at a tolerably equal angle, on the West towards the West, on 

 the South towards the South, and on the East towards the Eist. This arrange- 

 ment can only be accounted for on the supposition that the Longmynd was an 

 island standing out of the primeval sea, and that these Llandovery conglomerates 

 were formed from the debris of pre-existing rocks, and cast down on its slopes 

 under water. There was one other point he would also mention, and that was 

 the red beds below the Caradoo rocks. It would be very interesting to ascertain 

 with certainty the nature of these red beds. There were some doubts as to 

 whether they were Caradoc or Cambrians. It is not easy to correlate these rocks 

 accurately in a country so much fatxlted as this is. The conglomerate at the end 

 of Longmynd is certainly like that which occurs at Whartle Knowle, near 

 Hopesay. 



After the conclusion of the address and remarks upon it, these very 

 remarkable Ditches were again inspected and crossed with considerable diificulty. 

 The rain had been falling continuously for some time, and the visitors wound 

 round the hill under the guidance of Mr. Morris, through the open heathery 

 ground to the road leading to Clun. It was much too wet to attempt any close 

 examination of the botanical peculiarities of the district. With the kind assist- 

 ance of Mr. Morris, however, the fern hunters met with the lobed variety of 

 the prickly shield fern, Polystichum aculeatum, var. lobatum, in two localities, 

 and with the oak fern, growing in the ditches. The Lamb's lettuce, Fedia 

 olitoi-ia, was also gathered, and, rarer than all, the wild clove pink, Dianthua 

 caryophyllus, was gathered in a rocky lune about a nule above Olun. The 

 nodding bur-marigold, Bidens cernua, might also have been gathered, it was said, 

 had the weather been more favourable. Thus the way down the long lane to 

 Clun, full three weary miles, was pleasantly beguiled, and the travellers were 

 not sorry to reach the town. A tent had been erected on the Castle-green — the 

 tilt yard of olden times — and provisions made by mine host of the Buffalo for the 

 proper entertainment of his numerous hnngiy visitors. 



