DUMBARTONSHIRE EXCURSIONS. 23 
entrance to Strathleven, from which point the glen was followed 
up for about a mile. In the pond near Dumbarton Station, now 
part of the recreation ground, the nodding bur-marigold (Bidens 
cernua, L.) was observed. ‘This pond has since been cleaned out, 
and the species has, in consequence, become extinct in this 
locality. Near the entrance to the glen specimens of the great 
horsetail (Zguisetum Telmateia, Ehr.) were found growing. 
Murroch Glen is of great interest geologically, owing to the great 
height of the exposed sections of the strata through which the 
stream has cut its way. The rocks belong to the ‘cement stone” 
series of the upper division of the calciferous sandstones, and these 
here overlie the lower carboniferous sandstones, and are overlain 
by the carboniferous traps and lower carboniferous limestone. 
The exposed strata are composed of regularly alternating beds of 
limestone and marly shale, the continuity being broken at intervals 
by trap dykes. The sedimentary rocks were observed to be 
“charred” at some points by contact with the intrusive dolerite, 
this being specially noticeable where a vein of gypsum was 
affected. At a point a little over a mile above Murroch Farm 
the main stream is joined by a tributary coming from the eastward, 
the bed of which is cut across, near its junction with the Murroch 
Burn, by a trap dyke of considerable thickness, through which the 
water has cut a rather curious opening known as the ‘“ Gate of 
Sodom.” A small waterfall at one time existed here, but the basin 
has been filled by the detritus brought down by the stream up to 
the level of the dyke, the fall being consequently obliterated. 
The ring ousel (Zurdus torquatus) was seen in considerable 
numbers in the upper part of the glen. The chief plant of 
interest noted on this excursion was the wood vetch (Vicia 
sylvatica, Z.), a rare species in Clydesdale, which occurs in the 
glen. Other plants noted were the common agrimony (Agz7#- 
monia Eupatoria, L.) and the grass of Parnassus (Parnassia 
palustris, L.). A few members of the party made the return 
journey by way of Overtoun to the Dumbarton road, which was 
thence followed to Bowling. 
Overtoun was again visited by the Society on 28th March, 1896, 
in conjunction with the Natural History Society of Glasgow, when 
the many fine exotic shrubs in the gardens attracted particular 
attention. After leaving the policies, the party on this occasion 
