52 BRITISH AVONIAN CONODONT FAUNAS 
Summary 
Our overall Scottish correlations show a very close similarity to those proposed by 
Currie (1954, Table 1) on the basis of her goniatite studies. The only difference 
involves the first appearance of G. girtyi collinsoni subsp. nov. in the Middle Hosie 
Limestone of Fife. 
On the basis of this we have proposed the tentative correlation shown in Fig. 15, 
but it seems probable that the absence of this subspecies from underlying strata is 
the result of the relatively poor yields of the Lower Hosie (29 individual conodonts) 
and Hurlet Limestones (15 conodonts). 
This diagnostic subspecies is represented by less than 3 % of the total fauna of each 
of the two overlying Middle Hosie samples, each of which comprises more than 400 
identifiable conodonts. 
(e) Correlation of the Avonian with Europe and North America 
The purpose of this section is to discuss the value of conodonts in the correlation 
of the British type Avonian section with type sections in North America and Western 
Europe. The sections in the Mississippi Valley, the conodont faunas of which were 
described by Collinson, Scott & Rexroad (1962), are taken as standard sections for 
North America, and the West German Lower Carboniferous sections, the conodont 
faunas of which were described by Bischoff (1957) and Voges (1959), are taken as 
standard sections for Western Europe. We have also made provisional correlations 
with the Franco-Belgian Tournaisian Viséan succession, basing our comparisons on 
the faunas reported, but not described, by Conil, Lys and Mauvier (1964). 
The general results of this correlation are most gratifying. We have been able to 
suggest the relative equivalence of most of the various divisions of the North 
American, German, French, Belgian and British successions with a sufficient degree 
of confidence and precision to provide a satisfactory overall stratigraphic control. 
In those cases where our correlation is more tentative, we have discussed the limits of 
uncertainty, and these are seldom great. We have had the great advantage of 
working in virtually continuous Avonian rock sections, and some of the present 
anomalies between our faunal successions and those of other areas, such as Germany, 
and, to a lesser extent, the Mississippi Valley, probably lie in the scattered outcrops 
on which the latter are based. More information is needed from all areas before the 
present faunal similarities and differences can be fully interpreted. 
(i) North America and West Germany 
The K and Z Zones of the Avonian. 
The K and Z Zones of the Avonian are, in many respects, the most difficult part 
of the succession to correlate with other areas, largely because of the absence from 
them of some zonal species, and the presence of new genera and species which are, 
at present, not known with certainty from other areas. 
An important element of the K Zone fauna is the group of new species, which are 
confined to that zone ; these include Patrognathus variabilis gen. et sp. nov., Clyda- 
