The Tournaisian and early Visean (Carboniferous) faunas of Britain have been divided into a sequence of four assemblage biozones, the Vaughania vetus, Zaphrentites delanouei and Caninophyllum patulum assemblage biozones which are of Tournaisian age, and the Siphonophyllia cylindrica Assemblage Biozone of Visean (Chadian) age. This sequence of biozones established at Burrington Combe in the Mendips is used to correlate the Tournaisian and early Visean rocks from eight sections in the Bristol and South Wales areas. Several sections can be shown to be incomplete with a northward widening non-sequence present between the top of the Black Rock Limestone and the base of the succeeding Gully Oolite. One new species Sychnoelasma clevedonensis sp.n. and one new subspecies Caninophyllum patulum greeni sub-sp.n. are named.