HARD WICKE 'S S CIENCE - G OS SIP. 



63 



tiful scenes in nature. Although, in not a fev/ instances, 

 rich fossiliferous strata occur in unlovely places, amid 

 densely-populated neighbourhoods, as at the Wren's 

 Nest, near Dudley ; yet as a rule fossils are most 

 abundant where the rocks crop out along moun- 

 tain or hill sides or sea-cliffs. In searching for them he 

 startles the grouse or the moor-fowl, finds many a 

 lovely mountain plant solitarily blooming, and inhales 

 fresh air which seems to him like draughts of old 

 wine 1 Scenes of unsurpassed loveliness are thus re- 

 vealed to him, in the grandeur of rock-masses, or the 

 panoramic stretch of the valleys below and beyond. 

 What wonder if men who have had to toil the year 

 round for thebread which perisheth, in dingy offices or 

 amid the noise and bustle of machinery, should so value 

 the week or twoof summer holiday, which enables them 

 to devote themselves to those geological pursuits 

 which have all the charm and excitement of hunting 

 without any of its cruelty ! For, if the geologist wish 

 to change the area of his labours from the mountain- 

 side to the sea-side, he can do so at leisure, without 

 interfering with his success in fossil-hunting. Some 

 of the veiy best sections are those to be seen in our 

 sea-cliffs — some of the richest fossiliferous districts 

 are where the student may be taking in a fresh stock 

 of health whilst he is following his bent, and have 

 silently impressed on his memory scenes of beauty 

 which will last as long as his own individuality ! 

 Perhaps it is this direct contact with Nature in all her 

 varied moods which makes such enthusiasts of geolo- 

 gists. Not even botanists are more devoted to their 

 hobby; and it is undoubtedly this enthusiasm which 

 makes geological investigation not to depend upon 

 companionship for success. 



The recent absorption of most, if not all, the Lower 

 Silurian rocks into the Cambrian system has, of 

 course, largely added to the number of localities 

 where fossils are to be obtained. The Menevian beds 

 near St. David's, in South Wales, are exceedingly 

 rich in Trilobites ; among which Paradoxidcs Davidis, 

 the largest of its order, is abundant. This species 

 sometimes attains a length of two feet, and is, there- 

 fore, strongly contrastable in this respect with the 

 little Agnosttts {^g. 21) and i\\Q FhiUiJysia (fig. 54). 

 The South Welsh valleys are little explored, although 

 the geological student might do so to his double ad- 

 vantage, for they are equally rich in scenery and in 

 fossils. Monmouthshire presents an area of country 

 where we have, perhaps, a more varied geological 

 outcrop than anywhere else in Great Britain. Near 

 Newport a patch of Silurian strata abounds in several 

 species of Trilobites, notably Asaphus and Ogygia 

 (figs. 13 and 53). 



Maentrog and Port Madoc have long been cele- 

 brated for their rich yields of Trilobites. The student 

 may obtain them, in many places, from the slates 

 which build up the walls by the roadside, whilst in 

 the quarries there are usually bands or seams espe- 

 cially full of them. Few localities are better worth 



a visit, for we are here within the charming circle of 

 Snowdonia. The lower Lingula flags are well deve- 

 loped at Maentrog, and one Trilobite is so abun- 

 dant in them that it was proposed to call them 

 ^'■Olemis'''' beds. Two species of the obscure little 

 Agnostus are associated with it, along with various 

 other fossils. At no great distance up the higher 

 parts of the valley is Festiniog. A diminutive rail- 

 way, with cars of the same proportion as the narrow 

 diameter of its "permanent way," runs up one side 

 of the valley to Festiniog, and the geological student 

 can take advantage of it in his rambles, and thus pass 

 over the outcrop of beds rich in Trilobites. Another 

 locality for Cambrian Trilobites is the neighbourhood 

 of Dolgelly, a district whose magnificent scenery of 

 wild mountain and umbrageous valley is annually 

 drawing to it a larger number of tourists and visitors. 

 Here Conocoryphc, Agnostics, &c. may be found in 

 certain places in tolerable abundance. The student 

 might advantageously work his way to Dolgelly by 

 Tremadoc, at which place he will find abundant em- 

 ployment for his hammer. At the village of Pen- 

 morfa the slates are often crowded with remains of 

 Trilobites. Garth Hill is also a capital collecting- 

 ground. In many places the Llandeilo flags are so 

 full of Trilobites that Sir Roderick Murchison gave 

 them the name of " Trilobite Schists." Perhaps the 

 neighbourhood of Builth is the best place for obtaining 

 them. Several species of Ogygia occur, associated 

 with numerous other fossils. 



The Cambi'ian and Silurian rocks of the Lake dis- 

 trict are not so abundant in Trilobites as those of 

 North Wales and Shropshire, although we have 

 found them in the rich fossiliferous shales of Apple- 

 thwaite Common, and on the Lancashire side of 

 Windermere, — chiefly Asaphus. Calymene, Homalo- 

 notits, and others occur in the Dafton shales, of 

 Upper Llandeilo age. In the Coniston limestone, 

 also, we have Illtcmis, Chciriirus, Agnostus, &c., all 

 of them well-marked genera of Trilobites. 



In the Silurian proper (the upper Silurian of geolo- 

 gists only a few years ago), we find Trilobites reach- 

 ing their maximum of existence, both in genera, 

 species, and individuals ; and we have tolerably cer- 

 tain evidence that after this epoch they began to 

 decline until they became extinct. In the loveliest 

 parts of North Wales, as at Conway, the Devil's 

 Bridge (near Pentre Voelas), Craig Hir, and at 

 Mynydd Fronfrys, about four miles from Llangollen, 

 among the mountains, we find abundance of fossils, 

 and among them are various species of Phacops, 

 Calymene, &c. The pretty village of Woolhope, near 

 Hereford, is another charming collecting-ground, rich 

 in Upper Silurian fossils ; and here we find Ilhcniis, 

 Honialonotus, Phacops, &c. Trilobites are also abun- 

 dant in the Wenlock shales forming part of the 

 Malvern Hills. Of the Dudley limestone and its 

 treasury of these peculiar ancient forms of life, we 

 have already spoken. The neighbourhood of Ludlow 



