IX 
TH ATIGRAPH IC A L 
Note. 
/ 
P,y T. W. EDGEWORTH DAVID, B.A., F.R.S., 
Professor of Geology, University of Sydney. 
I —Introductory. 
The Foraminifera described in this Monograph by Mr. Frederick Chapman 
and Mr. Walter Howchin were found by my geological survey party on at least 
two distinct and widely separated horizons in our Permo-Carboniferous 
system. The Upper Horizon, that of Wollong, belongs to the Branxton Beds 
(Branxton Stage) of the Upper Marine Series, and the lower, that of Pokolbin, 
is to be referred to the Lochinvar Beds (Lochinvar Stage) of the Lower 
Marine Series (see section appended). 
The two foraminiferal horizons are separated from one another by a 
thickness of about 4,000 feet of strata, interstrati fied with which are the Greta 
Coal-Measures. The Wollong Foraminiferal Horizon is about 2,300 feet 
above the Greta Coal-Measures, whereas that of Pokolbin is about 1,700 feet 
below them. 
(a) At Pokolbin the Foraminifera occur in an earthy limestone 
through which are scattered small particles of volcanic rock. The limestone 
is fairly persistent on one particular horizon, and its outcrop can be traced 
continuously from a point a few chains east of Mr. J. MacDonald’s house, 
“ Ben Fan,” in Portion 86, Parish of Pokolbin, to Mr. William Wilkinson’s 
vineyard, “ Maluna,” in Portion 112 in the same parish, a distance of over 
three-quarters of a mile. It was at the latter locality that Mr. Eustace 
Wilkinson first called my attention to the outcrop of the limestone, which 
II.— Details of the Foraminiferal Horizons and 
Intermediate Strata. 
