68 Dr Hibbert on the Rocks of Shetland. 
course by a mass of epidotic, slenite, extending from Quendal 
Bay to Spiggie. In the next place, I described the sand- 
stone or granular quartz extending from Sumburgh Head to 
the Islands of Mousa, Bressay and Noss, distinguished by 
containing no apparent fragments of other rocks, as of gra- 
nite, quartz and felspar ; whilst to the west of it was a eonglo- 
merate sandstone, in which such portions were disseminated. 
This conglomerate sandstone was associated with another rock, 
consisting altogether of portions of other masses, as of granite, 
quartz, felspar, and occasionally of gneiss. The whole of these 
conglomerate strata were shown to rest, by their inferior edges 
upon the surface formed by the superior edges of a variety of 
strata, as of quartz, mica-slata, gneiss, limestone, &c. Lastly, 
were described the strata of the Cliff Hills, lying to the west of 
the conglomerate rocks and sandstone, consisting of clay-slate, 
whilst again, to the west of the clay-slate, were certain associated 
strata of quartz and hornblende-slate. All these strata were 
shewn to be in contact with the northerly bounding side of the 
epidotic sienite, which they met at an angle, or, in other words, 
by an attachment of their lateral edges. Again, the associated 
strata of quartz and hornblende-slate were found for a conside- 
rable distance to run nearly parallel to the strata of clay-slate, 
until, to the north of Scalloway, they began to be inflected 
to the eastward, so as to intercept, at Dale’s Ness, the whole of 
the strata of clay-slate. But certain other strata of quartz and 
hornblende-slate, appearing to the east at Dale’s Voe, and again, 
still more easterly at Rovie Head, occurring certain associated 
strata of quartz and limestone, these additional masses were re- 
presented in the character of nuclei, as affording attachments to 
new strata of clay-slate, which, in a more easterly direction, 
maintained a course from one apparent nucleus to another. 
I shall now continue my desciiption of the rocks in Shetland, 
in reference to the map annexed to this number, which is in- 
tended to represent a horizontal section of the country. Certain 
strata of limestone, will therefore be first noticed, situated to 
the west of those associated strata of quartz and hornblende 
which we had traced from Dunrossness. 
* For the reasons which induced me to adopt such new terms as mjierior^ in- 
ferior and lateral edges of strata, I beg leave to refer to the first part of my paper, 
which appeared in Number II. of this Journal, 
