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39° EXCURSION TO GLEN PARVA AND CROFT. pale flaggy rock, which, though not exposed at the surface, supplies the country rock in which the underground explorations. after copper have been worked. On the tip-heap from the main quarry no identifiable fossils have yet been recognised, but from the adit which has recently been driven in from the foot of the hill, farther to the north-east, numerous good specimens of Didy­ mograptus nicllOlsoni and se\'eral branching graptolites, indica­ tive of a horizon about the middle of the Arenig Series, have been obtained from a very similar type'of rock. The waste heap from the adit was examined, and yielded a considerable variety both of graptolites and mineralogical specimens. From the copper mine we returned to the main road, and" there meeting the carriages, drove along the edge of the Traeth Mawr alluvium to Aberglaslyn and Bethgelert, where we had tea at the Goat Hotel. Returning, we drove as far as the foot of the hill at Llanfrothen, and thence walked over, by the village of Rhyd back to Tan-y-bwlch. The scenery along this route is magnificent, but much more field work will have to be done before the details of the beauty of the area can receive a geological interpretation. EXCURSION TO GLEN PARVA AND CROFT (NEAR LEICESTER). THURSDAY, SEPTEMBER 2ND, 1909. Directors: W. KEAY and E. LOWE, F.G.S. Excursion Secretary: A. C. YOUNG. (Report by W. KEAY.) GL~N PAR VA. ADVANTAGE was taken of the cheap excursion to Leicester leaving St. Pancras at 10.6. On arrival at South Wigston Station from Leicester at 1.9 p.m., the party, numbering 2 I, proceeded to the brickyard at Glen Parva, a distance of rather less than half-a-mile. Fine weather prevailed, and this magnificent section of the whole of the Rh~tic Series was examined under conditions of comparative comfort. Standing on the eastern side of the clay pit, and looking westwards, the pit presents a face about 70 feet in depth. On the top, and immediately overlying the bluish shales of the Upper Rh~tic Series, is a reddish boulder clay, containing pebbles, Lias fragments, and a few boulders of syenite. Flints. are extremely rare. EXCURSION TO GLEN PARVA AND CROFT. 391: Immediately below the boulder clay is about 36 feet of blue and dark grey shales of the Upper and Lower Rhretic Series, interspersed with thin nodular bands of limestone, two only of which appear to be persistent throughout the exposure. At the base of the shales (the position of which is well indicated by a narrow ledge, formed by the workmen for drainage purposes) is the Bone-Bed which forms the base of the Rhretic Series. Underlying this, and affording strong contrast in colour,. is about IS feet of tea-green marls of the Upper Keuper Series, containing bands of sandstone. Below the tea-green marls, with a further colour contrast, is about 10 feet of red marl of the same series containing gypsum and bands of skerry. On the western side of the pit some denuding agent, pre­ sumably glacial action, has removed a few feet from the top of the Rh;;etic shales, so that the section on this side is incomplete. The continuity of the section, however, may be followed by observing the upper portion of the pit on the eastern side. Here the Rhretic shales are capped by a hard band of yellow limestone about two feet in thickness, forming the base of the Lowtr Lias, the zone of Ammonites (Psiloceras) planorbis. This Limestone is overlain by about one foot of Lower Lias. shale, covered by the red boulder clay to which previous reference has been made. Descending to the bottom of the pit by the steps near the office, the party were able to examine the section at closer quarters. Collections were made and specimens examined of the bright red gypsum, the skerry-bands and sandstone from the lower portion of the pit, and of the interesting concretionary nodules of limestone from the Rhretic above. Special attention was devoted to the Bone-Bed. Too thin to be of any lithological importance, its existence can be detected by its peculiar gritty nature. The party adopted the only successful plan of securing fossils from this bed by removing the gritty substance with its adhering shale en masse, to be washed, dried, and examined at leisure. Attention was called to a small dislocation on the south-east Side of the pit, with a throw of about 5 ft. The ascent of the pit having been made, the party proceeded to inspect the collection from the Bone-Bed made by the foreman, Mr. Pulford. The thanks of the party were cordially given to Mr. Pulford, and to the owners, for the assistance given in the examination of the section, and also to Messrs. Keay and Lowe for their guidance. The following is a list of the fossils which have been recorded from this section: EXCURSION TO GLEN PARVA AND CROFT. RHJETIC SERIES; Ophio!epis damesi, Avicu!a contor/a, Pecten va!oniensis, Isodonta ewa!dz~ Nucu!a variabi!is, Protocardium Phi!ippianum (C. rhaticum), Acrodus minimus, Gyro!epis alberti, Nemacanthus monilifir, Saurichthys acuminatus. LIAS: Ammonites planorbis. CROFT. Directors: F. W. BENNETT, M.Do\ B.Se.. and T. O. BOSWORTH, B.A., B.Se., F.G.S. (Report by Mr. BOSWORTH.) The train was taken to Croft, and the party at once pro­ ceeded to the syenite quarries, noticing on the way the narrow gorge where the Soar has encountered a spur of the syenite hill which must once have been buried in the Keuper Marl. From the N. side of the quarry a commanding view of the workings was obtained, and hert: a brief account of the relation between the Trias and the Charnian Rocks was given by Mr. Bosworth. He explained that the rising ground away towards the eastern horizon is formed by the outcrop of the Lias, and that we were now on the soft red Triassic deposits which form the great central plain of England. In this neighbourhood only the uppermost part of the Trias is known, and it rests directly on an old land surface of pre­ Cambrian rocks. In Charnwood Forest we see a considerable exposure of these old hills denuded of their Trias cover. But here at Croft, and likewise at Enderby, Earl Shilton, Stony Stanton and Sapcote, only just the summits of the buried hills are seen. In the deposits lying around these buried or partly buried hills, the direction of the dip is radial, and its steepness depends upon the angle of the buried slopes. The dip is well seen at the foot of the quarry incline. Another interesting feature is catenary bedding, seen where the marl occupies hollows in the old rock surface, and it seems likely that the larger valleys were filled up in the same way. An example was seen in the face of the workings. Moving on to that corner of the quarry which is nearest to Huncote, a rock surface was examined which had been partly overlain by Trias and partly by drift, but which was now uncovered by the workmen for quarrying. The portion which had been covered by Drift was smooth, bare and undulating, but the other was rugged, and bore projecting pitted knobs which were coated with a calcareous crust. Furthermore, the sub­ Triassic surface was seen to consist of unweathered syenite in a perfectly sound condition. EXCURSION TO GLEN PARVA AND CROFT. 393 From this place the party followed the footpath to Huncote Quarry. This working is in a portion of the hill which has been denuded of its Keuper cover and exposed to the British climate. Even at a considerable depth spheroidal weathering could be observed, whilst at the top a mass of syenite about 8 ft. thick is. exposed, so completely disintegrated that the .sand-martins have made nests in it. This formed a striking contrast to the sub­ Keuper surfaces, which are everywhere remarkable for the fresh condition of the rock. Indeed, the best stone is now obtained from beneath the marl. On the way back to the entrance of Croft Quarry the path passes over a small cutting in the Trias, where a six-foot bed of white and mottled sandstone is exposed. The grains of this. sandstone are so smooth and round that it is scarcely credible that the polishing could have taken place under water. The same bed was seen again in the quarry, and in a green skerry band a few feet below, salt pseudomorphs and ripple marks were observed, but no fossils have been found here. The south side of the quarry was next visited. Here twenty or thirty feet of marl have been removed from above the rocks and used for brick-making. Beneath the marl the rock surfaces are hummocky and worn in a manner highly suggestive of wind action, but the best examples have now been quarried away. In the marl, and especially at the base of it, there are many large stones worn into curious rugged shapes, fretted and pitted, and coated with a thin red crust. They are quite unlike beach pebbles and are all of the local syenite in sound, fresh condition. The bedding of the marl was then examined, and a discussion took place as to the possibility of such even, level bedding being produced in a desert. It was here stated by Mr. Bosworth that the finer material of the marl consists very largely of splintery quartz dust, but mixed with this fine material is much grit from the syenite, rounded grains of quartz, and much - worn garnets and other heavy minerals.

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