506 



MK. F. E.UTLEY 0]ST THE EOCKS 



a banded and an nnbanded series, and under the former will come 

 the different varieties of gneiss. For my own part, I am inclined to 

 regard the gneissic roeks of this district as probably being more or 

 less altered volcanic tuffs, or as sedimentary rocks mainly composed 

 of eruptive material derived from the disintegration of rocks of a 

 dioritic or syenitic character. Reasons for and against the assump- 

 tion of a sedimentary origin for these gneissic rocks have already 

 been given in the first part of this paper, and a section through the 

 Malvern Hills was appended, based upon the hypothesis that folia- 

 tion in this district corresponded with structural planes which fre- 

 quently mark lithological differences, and that these structural 

 planes were possibly planes of stratification. We shall find, on 

 comparing the results of the foregoing microscopic examination, 

 that, except in that part of the range which lies south of the fault 

 crossing Swinyard's Hill, the rocks are of a mixed character, being 

 partly foliated and. partly devoid of foliation. In the following Table 

 the rocks are placed in three columns, so as to divide the eruptive, 

 the foliated, and the probably and unquestionably stratified rocks : — 





Eruptive. Foliated. 



Stratified. 



North Hill 



North Hill 



North Hill (above West 



Malvern) 



North Hill (The Dingle) 

 Worcestershire Beacon 

 t 



Herefordshire Beacon . 

 Swinyard's Hill 



i 



tt 



Hornblende-Gabbro, 



Diorite. 

 Quartz- Syenite. 



Mica-Diorite. 



Mica-Diorite. 



Granuiite?, Granite, 

 Diorite, Epidosite ? 



* Eucrite, * Basalt, 

 * Devitrified Obsi- 

 dian. 



Pegmatite, Horn- 

 blende - Pegmatite, 

 Diorite. 



Diabase. 



Gneissic Syenite, 

 Gneissic Diorite. 



Biotite-Gneiss. 



Hornblendic Gneiss. 



Biotite-Gneiss, Bio- 

 tite, Muscovite- 

 Gneiss. 



Mica-Schist, Mica- 

 ceous Quartzite- 

 Schist. 



Altered Tuff? 



Diabase-Tuff? 



Altered Sand- 

 stone, Quart- 

 zite. 



t Poets between a Little south of the summit of the Worcestershire Beacon 

 on to Winds Point were not collected. 



j Pocks of Midsummer Hill were not collected, 

 tt Pocks of Keys End were not collected. 



* These occur in the eastern buttress of the Herefordshire Beacon, and are 

 of Cambrian (?) age, "Altered primordial rocks " of Dr. Holl. 



It is evident therefore that the above list gives only a very in- 

 complete idea of the rocks constituting the whole length of the range. 

 By reference to Dr. Holl's paper, these gaps may, to some extent, 

 be filled up, as already indicated in the first part of this communi- 

 cation. From the tabular classification just given, it appears that 

 the North Hill consists partly of rocks which show no foliation, and 

 which we must regard as truly eruptive, and partly of foliated rocks, 



