NEW SPECIES OF PELECYPODS. 
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9 
NEW SPECIES OF PELECYPODS FROM THE CRETACEOUS 
OF NORTHERN ALBERTA. 
By F. H, McLearn. 
INTRODUCTION, 
The species described below are in part from the Colorado group and 
in part from a group of Lower Cretaceous 1 age. The Colorado, as here 
delimited, includes the Pelican shale, Pelican sandstone, and Lower La 
Biche formation in the Athabaska valley; and the St. John and Dunvegan 
formations and the lower shale and Bad Heart sandstone members of the 
Smoky River formation in the Peace valley. The group of Lower Creta- 
ceous age embraces the McMurray tar sands, Clearwater and Grand 
Rapids formations in the Athabaska valley, and the Loon River and Peace 
River formations in the Peace valley. 
Acknowledgment is made to Dr. T. W. Stanton for advice in the inter- 
pretation of the fossils. 
DESCRIPTION OF SPECIES. 
Order, Priondesmacea Dali. 
Family, nuculid® Adams. 
Genus, Nucula Lamarck. 
Nucula dowlingi n. sp. 
Plate III, figures 1, 2. 
Description , In general form and radiating surface sculpture this 
species Resembles Nucula pectinata Sowerby, from the British Gault 
formation; but the beaks are consistently even more posterior in position 
and curve backward. Compared with the Montanan species N . cancellata 
Meek and Hayden, the beaks of the St. John species are more posterior in 
position and the lunule is relatively broader. Height 15 mm., length 19 
mm This species is named after D. B. Dowling of the Geological Survey, 
Canada. 
Horizon. Common in the St. John formation, below Cache creek on 
Peace river, British Columbia. 
Collection. Victoria Memorial Museum; holotype, Cat. No. 5394. 
Family, parallelodontid® Dali. 
Genus, Dicranodonta Woods. 
Dicranodonta dowlingi n. sp. 
Plate III, figures 3, 4, and 5. 
Description. The nearest species is Dicranodonta ' obliqua (Keeping) 
from the lower Greensand (Aptian) of Upware; compared with it the 
Peace River species is larger, more obtuse, not flattened centrally, has a 
* Un the sense of pre-Cenomanian Cretaceous. 
