258 W. N. LOGAN 
Yellowstone Park.7—The thickness of the formation for this area 
is placed at 200 feet. It consists of sandstones, marls, limestones, 
and clays, and contains, according to Stanton,’ the following spe- 
cies: Pentacrinus astericus M. & H.; Rhynchonella myrina Hall & 
Whitf.; Rynchonella gnathophora M.; Ostrea strigilecula White ; 
Ostrea engelmant M.; Gryphea planoconvexa Whitt.; Gryphea calceola 
var. nebrascensis M. & H.; Lima cinnabarensis Stan.; Camptonectes 
bellistriatus M.; Camptonectes bellistriatus var. distans Stanton; Camp- 
tonectes pertenurstriatus Hall & Whitf.; Camptonectes platessiformts 
White; Avzcula (Oxytoma) Wyomingensis Stan.; Pseudomonotis 
Curta (Hall)?; Gervilha montanaensis M.; Gervillia sp. Stan.; 
Modiola subimbricata Meek; Pinna kingt M.; Cucullaea haguet M.; 
Trigonia americana M.; Trigonia elegantissima M.; Trigonia mon- 
tanaensis M.; Astarte mecki Stan.; Astarte sp. Stanton; Tancredia? 
knowltont Stan.; Protocardia shumardi M. & H.; Cyprina? Cinna- 
barensis Stanton; Cyprina? iddingst Stanton; Cypricardia? haguet 
Stanton; Pholadomya kingi M.; Pholadomya tnaequiplicata Stan.; 
Homomya gallatinensis Stan.; Pleuromya subcompressa M.; Thracta 
weedi Stanton; Thracia? montanaensis (Meek)?; Anatina ( Cer- 
comya) punctata Stan.; Anatina (Cercomya) sp. Stan.; Neritina 
wyomingensis Stan.; Lyosoma powelli White; Turitella sp. Stan.; 
Natica sp. Stan.; Oppelia? sp. Stan.; Perispinctes sp. Stan.; and 
Belemnites densus Meek and Hayden. 
THE CANADIAN AREA 
In the Queen Charlotte Islands Whiteaves3 noted the occur- 
rence of the following species, which are common to the Jura of 
the Interior: Pleuromya subcompressa Mk.; Astarte packardi White ; 
Avicula (Oxytoma) mucronata Mk.; Gryphea calceola var. nebras- 
censis M. & H.; Lyosoma powelli White ; Belemnites densus M.& H.; 
Belemnites skidgatensis Whiteav.; Grammatodon inornatus Whiteav.; 
Modiola subimbricata Mk.; and Camptonectes extenuatus Mk. 
Although Whiteaves recognized the interior affinity of these 
forms, he was inclined to put both groups into the Cretaceous 
tU.S. Geol. Surv., Yellowstone Park Folio, 1896. 
2U. S. Geol. Surv., Yellowstone Park Monograph, XXXII, p. 601, 1899. 
3 Geol. Surv., Canada, Mesozoic Fossils, Vol. I. 
