NOKTH-WEST KKGION OK ClIAKMWOOl) FOREST. 99 



impressed a cleavage on the finer-grained stratified rocks *. Dio- 

 rites were intruded into Cambrian rocks, probably before the 

 Carboniferous period, in the Hartshill district, but these have no 

 particular affinity with the larger masses in the Porest. Certain 

 fragments in the Permian breccias of Leicestershire indicate the 

 existence of red felstones somewhere in the neighbourhood, which 

 do not correspond with any now visible above ground. It is, 

 indeed, very possible that intrusions of melted rock occurred at 

 several epochs, terminating with the post-Carboniferous basalt, 

 such as that found in the Whitwick pit-sinkings, and that the 

 igneous rocks of the Porest are of more than one age ; but beyond 

 the statement that we think the above-named masses anterior to 

 the great earth-movements which seem to have afi'ected a very 

 large area of the Midlands, we feel unable to venture t- 



14. Corrigenda. — Had we to rewrite our former papers, w^e should 

 make many small changes in phrases and words. Por instance, the 

 epithets " blue " and " bluish " used of various rocks should rather be 

 •*' purple " and " purplish." " Schist" and " schistose " have been used 

 very loosely in Part I. % The improper designation of the Black- 

 brook Group as " quartzites " was corrected in Part III. This was 

 inherited from previous writers on Charnwood ; so also were many 

 phrases which describe the rocks as much metamorphosed, or as if 

 they had suffered great changes by the action of beat. In one case, 

 however, where the rock is described as "intensely altered" § the 

 specimen on which the description was founded turns out to have 

 been broken from an included fragment, so huge as to have been 

 mistaken for the natural rock. 



Mistakes are fortunately not very numerous. In Part I. p. 755, 

 line 7, "North-eastern" should be "North-western"; p. 762, fig. I, 

 "Branch" is an uncorrected misprint for " Brande." In fig. 2, the 



* As at Brazil Wood, at Whittle Hill, Bradgate, and possibly at Steward's 

 Hay ; also (if the rock be a dyke) at the Stable Quarry, Bradgate. Mr. J. D. 

 Paul, in a good report of a visit of the Geologists' Association excursion to 

 Charnwood (Proc. Geol. Assoc, vol. x. (1888) p. 472), says that Charnwood 

 presents in miniature all the features of a mountain-chain, and generalizes from 

 the fact that the outbursts of intrusive igneous rock occur at a considerable 

 distance from the anticlinal and near the foot of tlie hills. But the vertical 

 diflference is hardly enough to warrant any generalization, and the intrusive 

 rocks appear to us more probably anterior to the ' mountain-making.' 



t Mr. W. J. Harrison expresses the opinion that the 'syenite' at Enderby is 

 intrusive in beds probably of Cambrian age. His A'iew may be correct, but we 

 have seen nothing to separate the rock described by us as occurring there fi-oni 

 some of those in the Forest. He also states that the rock struck in the Ortou 

 boi'ing appears to be identical with the quartz -felsite of tlie Caldicote Pit, 

 Nuneaton. To us the two rocks appear dissimilar. The Orton rock, however, 

 is indistinguishable from the Sharpley rock, both macroscopically and micro- 

 scopically, except that we liad less hesitation in recognizing it as a true lava. 

 This is a point of great interest, for it shows the occurrence of another (probably 

 contemporaneous) volcano, and greatly extends the area affected by the pre- 

 Carboniferous earth-movements. Orton is more than 30 miles S.E. of Sharploy, 

 and about 25 miles from the nearest point of the Forest. 



\ Quart. Jouru. Geol. Soc. vol. xxxiii. { 1877). § Op. at. p. 778. 



