16d PEACH : NOTES FOK THE FIELD EXCUHSIOX TO MELUOSE. 
of pink chert or carnelian occurs on tlie liorizon of the Cornstone 
at tlic top of the Upper Old Red. just underlying a series of basic 
lavas on the horizon of the Kelso Traps."' The Cornstone itself, 
which is associated witli tlic chert, should be studied, as it is a 
conspicuous band which occurs intermittently from this point 
to Carham-on-Tweed to the east, and also very much further 
to the west as far as Kirkcudbrightshire. There is a peculiar 
ash associated with the lavas in this region. It is full of little 
pellets of ha?matite or limonite. In this region the necks of 
the Maiden Paps or Greatmoor could prehaps be visited during 
tlie one excursion. 
Note about the Eildon and Black Hill Trachytes. 
It should be remembered while studying these rocks that 
almost all over the south and west of Scotland the earliest lava 
flows are very basic, such as olivine basalts, limburgites, etc. 
Tiiese occur just at the top of the Upper Old Red beds or at the 
very base of the Carboniferous. They are generally succeeded 
by andesitic basalts and andcsites, and in several places, such as 
the Garleton Hills, the Campsie Fells, and the Renfrewshire 
Hills, the latest rocks reach the stage of trachytes, phonolites, 
and nepheline-bearing rocks. 
The Kelso traps, as can be seen, are all very basic, and 
their horizon is distinctly marked. The Eildons and the other 
intrusions evidently belong to the latest phases of the Low^er 
Carboniferous volcanoes. Plenty of evidence on this point is 
alforded by the fragments of cement-stone and limestone that 
have fallen back into the numerous necks that are associated with 
their trachytic rocks. 
VIII. Arenig jaspers and cherts associated with the Lower 
Silurian rocks, haggis rocks, and greywackes of the Southern 
Uplands. 
Take train up Gala Water to Heriot Station. Cross to 
w^est side of them. Walk back one mile down Gala Water to 
past the mouth of Heriot Water and Casohope Burn. In the 
corner of a field west of road on southern outcrop of black shale, 
shown on map 25, see outcrop of jasper associated with grey 
