93 
beds on Castle river and also in the much lower Hillcrest Unio bed, sug- 
gesting a fairly long range in the formation for this species. C. ? onestae 
is found in the beds at 520 feet on Lyon creek and in the Unio bed south 
of Hillcrest. The earliest faunule, at 230 feet on Lyon creek, has nothing 
exactly in common with the other faunules, but the U. cf. hamili is very 
close to U. hamili in the Unio bed south of Hillcrest and may be merely a 
variety of it. 
This freshwater invertebrate fauna is not known anywhere to extend 
as high as the strata carrying the upper dicotyledonous flora, but is coeval 
with the lower or primitive flora. 
INOCERAMUS LABIATUS FAUNA? 
In the United States interior, although it occurs rarely in the zone of 
Prionotropis , Inoceramus labiatus Schlotheim is only common in earlier 
beds where it forms a well-defined zone, recognizable over a considerable 
area. 1 It cannot, as yet, be definitely stated whether or not this zone is 
represented in southwestern Alberta. In shales on Mill creek, some dist- 
ance south of both the Blairmore and South Fork areas, Inoceramus 
labiatus is very common and no Prionotropis has been found with it. 
Unfortunately it has not been possible, so far, to establish the stratigraphic 
position of these /. labiatus beds with relation to the Prionotropis beds; 
for this reason, the existence of a pr e~Prionotropis zone of I. labiatus in this 
region cannot at present be proved. No beds containing common I. labiatus 
have yet been located in the Blairmore or South Fork areas, the nearest 
occurrence being in the above-mentioned Mill Creek locality. But if such 
a zone exists it would be in the Colorado shale, below the Prionotropis zone, 
near Well’s crossing on Castle river, and in the basal concealed part of the 
Crowsnest Biver section of the Colorado shale, west of the Blairmore 
sheet. 
PRIONOTEOPIS FAUNA 
The Prionotropis fauna was found at only one locality, at Well's 
crossing, on the north bank of Castle river. There thin-bedded sandstones 
and arenaceous shales carry : 
Prionotropis sp. 
Inoceramus sp. 
Trails. 
The Prionotropis sp. is near. P. woolgari as identified in North Ameri- 
ican faunas. The beds containing this fauna are about 150 feet below a 
prominent sandstone band which Rose considers the equivalent of the 
sandstone band at the base of the exposed section on Crowsnest river west 
of the Blairmore map-area; they may, therefore, be equivalent to some of 
the concealed beds at the base of the Crowsnest River section. 
SCAPHITES VENTRICOSUS FAUNA 
The Scaphites ventricosus fauna is best preserved in the section exposed 
along Crowsnest river west of the Blairmore map-area and east of Crows- 
nest lake. At the bottom, 600 feet are concealed between the highest 
outcrop of Crowsnest volcanics and the lowest outcrop of the Colorado shale. 
Above follow about 1,650 feet of Colorado shale in numerous exposures. 
1 Reeside, J. B., jun.: U.S. Geol. Surv., Prof. Pap. 132B, p. 28 (1923). 
77885— 7J 
