254 Proceedings of the Royal Physical Society. 
very rarely met with. By far the most abundant relics are 
the caudal shields, or ;pygidia, which are sometimes found 
two or three lying together on one small piece of shale. 
The head is of rarer occurrence ; it is sometimes found en- 
tire, but very frequently disjointed, the glabella, or central 
part, lying apart from the two lateral cephalic shields. Of 
entire trilobites I found one very good specimen (in the ex- 
tended position) at Wilkieston, and two doubled or rolled 
up (after the manner of certain Oniscidce when alarmed). 
Mr Walker, of the University Museum, St Andrews, showed 
me also a very good specimen of the entire animal extended, 
which he obtained at Ladeddie. 
Ill, Note on the Exposure of the Liberton Old Red Sandstone Conglome- 
rate Bedy in a Quarry recently opened near the Grange House, New- 
ington. By Andrew Taylor, Esq. 
The existence of the conglomerate, only visible for a few 
yards at Liberton Brae, and sinking to the E.S.E. at about 
35°, was noted, so far back as 1839, by Cunningham, in his 
prize essay on the Geology of the Lothians. In the excellent 
descriptive catalogue of the rock specimens in the Jermyn 
Street Museum, Mr Geikie catalogues this rock as a cal- 
careous conglomerate ; being one of the passage beds between 
the Old Ked Sandstone and Lower Carboniferous series ; the 
basis being stated to be a calcareous sand, with the pebbles 
generally well rounded, and consisting partly of a compact, 
cherty limestone, partly of different felstones, and sometimes 
of various gray micaceous grits. The stratigraphical import- 
ance of this bed in our local geology has likewise been duly 
recognised in the recently published geological survey map 
of the district ; in which it has a distinctive colour and boun- 
dary assigned to it, which is made to terminate at the margin 
of the great fault, marked as running from the northern base 
of the Pentland range to near Wester Duddingston. The 
strata north of this fault-line, and on which Newington with 
the rest of the city is built, are, on the other hand, pectorially 
distinguished as decidedly Lower Carboniferous, and beneath 
the horizon of the Burdiehouse limestone. In the field to the 
west of that section of the Lover s Loan which runs past the 
