644 KEroRT — 1881. 



instance, where they rested on the chloritic schists, •which -were seen under the 

 microscope to consist of a fine i'elspathic mud, nut only did frag-ments of this rock 

 occur in the conglomerate, but much of its material was found finely comminuted 

 in the matrix of the overlying series. Occasionally some way up in the basement- 

 beds, bands of large felsite pebbles were found, showing the drifting of the shingle 

 now and then from the more distant rocks of the felsitic series or Uinorwig Beds. 

 On the whole he considered that it was quite clear that the quartz-jasper con- 

 glomerates and the felsite conglomerates belonged to the same series, and formed 

 part of the basement-beds of the Cambrian. 



14. On the Gnarled Serlett of Aiuhcch and Hohjlieod. in Anrjlesea. 

 Bij Professor T. McK. Hughes, M.A., F.G.8. 



The author oflers the results of his inquiries into the age of certain schists 

 which form the main mass of the rocks of Northern and Western Anglesea, 

 leaving for the present the consideration of two masses of somewhat similar rock 

 which occur S. of the Llaufaelog gneissic axis in the central and south-eastern part 

 of the island. 



The two views hitherto current as fo their position were: 



1. The metamorphic theory of Professor Ramsaj', who referred them to 

 altered Cambrian and Silurian. 



2. The view of Dr. Ilicks and others, who considered them to be the upper 

 part of the Archasan rocks. 



The author offers a third explanation, which he calls at present only a good 

 working hypothesis, but for which be thinks tliat the evidence he has already col- 

 lected makes out a strong probability. 



He uses the term metamorphic for those rocks onlv in wliicli there has becM 

 a complete re-arrangement of the constituent minerals, and excludes therefore all 

 merely consolidated matter, though crystallised as limestones, compacted as quartzite 

 or veined, or filled with replacing minerals, as chert, or crumpled, which he con- 

 siders merely an accident which may ha](peu to an ordinary sedimentary or to a 

 metamorphic rock, and the cause and mode of occurrence of which he explains. 



The difficulty with regard to the Amlwch and Holyhead beds arose from 

 considering them metamorphic, an impression derived from their gnarled and con- 

 torted appearance. He describes tlie sequence commonly found among the lower 

 beds of the series, from the constancy of which he infers that no large mass of 

 them is faulted out of sight in the Amlwch district. He points out the agreement 

 of these sections with some of those in the Holjdiead area. lie gives a number of 

 sections along the border country between them and the black slates, which seem 

 to indicate a passage up from the slates into satiny beds, which when consisting 

 of rapid alternations of soft material, and hard unyielding bands, become contorted 

 and gnarled. 



If these sections cannot be explained away, the felspathic gnarled rocks must 

 be either the marine equivalents of the Bala volcanic series, or the result of a later 

 (probably Silurian) denudation of those beds. As Lower Mny Hill ( =Birkhill) 

 fossils only occur in the slates immediately south of the area in question, the latter 

 supposition is the only one tenable in the present state of the evidence. 



15. The Suhjed-inatier of Geology, and its Classification, 

 By Professor W." J. Sollas, M.A., F.G.S. 



The object of this paper is to remove certain prevailing misconceptions on the 

 aim and scope of Geology. The accepted definition of Geology as ' the history of 

 the earth's crust and the fossils it contains ' is shown to be both too wide and too 

 narrow ; too wide since it includes Paheontology, which so far as it is a study of 

 forms f life belongs to Biology, and too narrow since the science of the whole 

 earth necessarily embraces much more than a study of its crust. Geology is one 

 of a group of three concrete sciences, which are Astronomy, Geology, and Biology. 

 The scope of Geology, as the science of the earth, is so wide that a "fresh classifica- 



