40 
B. acutus , B. Murchxsonia , Gyrogonia , and Modiolopsis 
orbicularis. On crossing over the brook, by the step¬ 
ping-stones, at the further end of the Common, a large 
quarry of Bala limestone is reached, upon the side of 
the turnpike road to Bishop’s Castle, the beds of which 
are pitched up almost vertically,' and they contain, 
along with many other organic remains, a new species 
of Lingula , in great numbers. On the lower side of the 
quarry, the very bottom beds of the Caradoc can be 
examined, and they are well worth hunting in, as they 
contain a great number of fossils, nearly every one of 
which is a new species not yet named. 
The Longmynd Rocks, the lowest sedimentary form¬ 
ation, are exposed on a grand scale in many extensive 
sections on the hills from whence they take their name. 
These rocks were considered unfossiliferous until Mr. 
Salter discovered lately one specimen of what he believed 
to be a portion of a Trilobite , and named Palceopyge 
Ramsayi (I have been fortunate enough to find another 
small portion of this ancient crustacean), also two 
different species of Annelides, named by him Arenicola 
didyma , and Arenicola sparsa . The best preserved 
specimens of Arenicola are to be procured in some blue 
slaty stone close by a path winding round the Yearling 
Hill, a little distance above the stream that runs down 
the valley facing Little Stretton ; there also are some 
very perfect impressions of rain drops and ripple mark¬ 
ings. Mr. Salter found his Trilobite on the summit of 
the Round Hill; I found mine close to the Packet 
Stone, above Minton, both places lying on the same 
horizon of beds. The Caradoc conglomerate, which 
encircles the base of these hills, is composed of a 
multitude of angular stones from older formations, 
which were probably carried there by icebergs, and 
then being stranded along the edge of these primeval 
islands of the Longmynds, gradually melted and 
