No. 3.] HUNT — ON CAMBRIAN AND SILURIAN. 299 



time recognized among specimens supposed to be from the same 

 horizon. It has since been described as P. Hicksii, and found 

 to belong to the basal beds of the Lingula flags, — the Menevian 

 group. 



Upon the flanks of the Malvern Hills there are found resting 

 upon the ancient crystalline rocks of the region, and overlaid 

 by the Pentamerus beds of the May Hill sandstone (originally 

 called Caradoc by Murchison) a series of fossiliferous beds. 

 These consist in their lowest part of about 600 feet of greenish 

 sandstone, -which have since yielded an OholtlJa and Serjndifes, 

 and are overlaid by 500 feet of black schists. In these, in 1842, 

 Prof. John Phillips found the remains of trilobites, which he sub- 

 sequently described, in 1848, as three species of Olenus. [Mem. 

 Geol. Survey II, part 1, 55.] These black shales, which had 

 not at that time furnished any organic remains, were by Murchi- 

 son in his SilurijD System (p. 416) in 1839 compared to the 

 supposed passage-beds in Caermarthenshire between the Llan- 

 deilo and the Cambrian (Bala) rocks; which, as we have seen, 

 were newer and not older strata than the Llandeilo flaas. From 

 their lithological characters, and their relations to the Pentamerus 

 beds, these lower fossiliferous strata of Malvern were subsequently 

 referred by the Government geologists to the hoi'izon of the 

 Caradoc proper or Bala group; nor was it until 1851, that their 

 true geological age and significance were made known. In that 

 year, Barrande, fie^h from the study of the older rocks of the 

 continent, came to England for the purpose of comparing the 

 British fossils with those of the primordial zone, which he had 

 established in Bohemia and Scandinavia, and which he at once 

 recognized in the Lingula-flags of Sedgwick and in the black 

 schists at Malvern ; both of which were characterized by the pre- 

 sence of the genus Ohnus, and were referred to the horizon of his 

 Etage C. This important conclusion was announced by Salter 

 to the British Association at Belfast in 1852. [Hep. Brit. Assoc, 

 abstracts, p. 56, and Bull. Soc. Geol. de Fr. II, xvi, 537.] 

 Since that time the progress of investigation in the Middle and 

 Lower Cambrian rocks of Wales has shown a fauna the impor- 

 tance and richness of which has increased from year to year. 



The paleontological studies of Salter, while they confirmed the 

 primordial character of the whole of the great mass of strata 

 which make up the Middle Cambrian or Festiniog group of Sedg- 

 wick, (consisting of the Lingula-flags and the Tremadoc slates,) 



