108 THE CAMBRIAN, EIC. OF THE MALVERN HILLS. [ Feb. 1902. 
labelled ‘ Upper Black Shale”! Mr. Matley recognizes the following :— 
Acrotreta sp., cf. A. socialis (figs. 15 & 16, p. 144); Lengulella sp., ef. 
L, petalon (figs. 7 & 8, p. 141), and Linnarssonia Belti(?). In precisely 
similar pieces of shale in the Worcester Museum, labelled ‘ Black 
Shale,’ Mr. Matley finds Acrotreta sp., cf. A. socialis, and Lingulella(?) 
sp. The same collection contains an imperfect Olenid and Hyolithus 
assulatus, sp. nov. (fig. 26, p.119), which probably came from a dark 
band in the Bronsil Shales. In the Museum of Practical Geology, 
Jermyn Street, specimens labelled ‘ Dictyonema-shale ’ include Obo- 
lella(?) Saltert, Lingulella sp., cf. L. petalon, and Linnarssonia Belti 
(figs. 17 & 18, p.145). In the collection belonging to the Malvern 
Field Naturalists’ Club at Malvern College are fragments of Grey 
Shale containing the following :—Cheirurus Frederic: (figs. 27 & 28, 
p. 120); an Agnostus indistinguishable from A. dua, Call.; an 
Asaphid (Platypeltis Croftti?); and an imperfect Olenid. Dr. Calla- 
way is stated * to have recognized Macrocystella Marie, Call, in a 
piece of grey shale in the collection of the late Dr. Piper; but no 
specimens referable to this form appeared to exist when I examined 
the collection shortly before Dr. Piper’s death, and Dr. Callaway 
informs me that he has no recollection of ever seeing the specimen 
in question. 
The fauna of the Bronsil Shales may, for the present, stand as 
shown in the table on p. 110. 
With regard to their lithology, the shales are of a light bluish-, 
greenish-, or yellowish-grey colour, micaceous, and very fissile, but 
apparently of somewhat coarser grain than the Black Shales, and at 
the same time firmer and less closely jointed. Some dark-grey 
shales occur in the Coal-Hill igneous band. 
The total thickness of the Bronsil Shales and diabases may be put 
down at about 1300 feet (it is possibly even greater at the extreme 
southern end of the district); andif, out of the 550 feet representing 
the combined thickness of the two igneous bands, 250 feet be attri- 
buted to the shales, the total thickness of the Bronsil Shales alone 
will amount to 1000 feet, and that of the diabases and basalts to 
300 feet. It is, however, necessary to note that higher beds of the 
original series have almost certainly been removed by the denudation 
which preceded the deposition of the May-Hill Sandstone; so that 
the Tremadoc Series may have been originally more than 1000 feet 
thick. It is possible, indeed, that some of these upper beds still 
remain uncovered by the May-Hill Sandstone at the southern end 
of this district, though not exposed, and that the Upper Grey 
Shales may be more than 500 feet thick. 
1 The term ‘ Upper Black Shale’ refers to the Bronsil Shales (Grey Shales). 
I have not succeeded in finding a rock that quite agrees in character with these 
pieces, either in the Black or Grey Shales; but, apart from their rather dark 
colour, the fragments resemble the Grey rather than the Black Shales. 
2 Geol. Assoc. Rec. of Excurs. 1860-1890 (1891) p. 412. 
