92 The American Geologist. Anpust, i89i 
ian (Intumescens-kalk) species occurring at Brilon, Westphalia.* 
Fish remains are sparingly found, {Palceoniscus devontcus, Acan^ 
thodes.^ prisons, and several undetermined species) with occasional 
fragments of Lepidodtndron and other plants. The shales ly- 
ing between and above these bituminous bands became filled up- 
ward with increasing amounts of sandstone until graduall}' and 
finally the thin-bedded sandstones predominate over the shales. 
It was to this portion of the Portage series that the term " Gar- 
deau or Lower Fucoidal group " was originalh' applied, and to the 
upper and overl3-iug beds which are mostly heavier bedded sand- 
stones, the name "Portage or Upper Fucoidal group." The fact 
is that the alteration in the lithological nature of the sediments 
has been a ver}' gradual evolution and it is quite impossible to 
uphold a satisfactory division of the series on such a basis. The 
palivontological evidence is diflferent. AVith the introduction of 
the green shales of the Cashaqua or basal division of the series, 
we find certain species of the Styliola fauna reappearing. These 
become more abundant or are at least better retained in the beds 
of shales lying between the first and second bituminous bands or 
wherever there is suflflcient calcareous matter in the strata to form 
subcoucretionar}' lenticles. 
It is here that the fauna attains its highest and most character- 
istic development, but so far forth as the shales prevail, even 
after the very material encroachment of the more arenaceous sedi- 
ments, the same fauna accompanies it. We refer to the fauna in 
its toute ensemhh', the variations in the faunules of a given stratum 
from that of the next above or below being of limited significance 
either geologically or palffioutologically. In the lower beds the 
species of the shales are occasionalh- found in inferior preserva- 
tion, in the thin layers of sandstone, but as the sandstones become 
heavy-l)edded and more continuous, this is a rare occurrence. 
Reference has been made in Bulletin No. IG, (p 68) to the appear^ 
ance in the midst of the "Portage" sandstones, that is, in the 
upper member of the series lying between the Grenesee shales and 
the Chemung sandstones, and about 600 feet below the earliest 
known occurrence in this section of a fauna with Spirifer dis^ 
juncfns and Orthis impressa, of an assemblage of brachiopods, 
Leiorhynchus mesacostalis, Amhocoelia nmbonata, Atryp<t asperriy 
RhynchoneUa eximia, etc., which are a new association and one 
*Kayser. Zeitschr. der deutsch. gcolog. Gesollsch. vol. xxiv, p. 007, 
1872. 
