118 
MUSEUM BULLETIN NO. 2. 
bedded limestone” and referred to the Middle Cambrian; and 
(d) in China it occurs well up in the Middle Cambrian. 
The affiliations of the species constituting the Albertella fauna 
are nearly all with those of the Middle Cambrian. The fauna 
abounds in types not found in the Lower Cambrian, and while 
several of them are undescribed the following list of described 
species will be sufficient for the purposes of our study: — 
Described Species of Albertella Fauna. 
Mount Bosworth. 
Dearborn river. 
British Columbia. 
Montana. 
Micromitra ( Paterina ) wapta Walcott 
X 
Micromitra ( Iphidella ) pannula (White)... . 
X 
Obolus parvus Walcott 
X 
Obolus ( Westonia ) ella (Hall and Whitfield) 
Acrothele colleni Walcott 
X 
X 
X 
Acrothele panderi Walcott 
X 
W im.aup.Hn simplex. (Walcott 1 
X 
X 
Olenopsis agnesensis Walcott 
X 
Olcnopsis ameriainvs Walcott 
X 
Albertella bosworthi Walcott 
X 
Albertella helcna Walcott 
X 
X 
Bathyuriscusproductus (Hall and Whitfield) 
X 
Micromitra ( Tphidella ) pannula has been identified from forty- 
one Cambrian localities 1 of which ten have been referred to the 
lower division of that system. Three of these are from the Pioche 
formation and one from the Albertella fauna. Micromitra 
(Paterina) wapta 2 and Obolus parvus 3 are confined to beds to 
which the Albertella fauna has been referred in British Columbia. 
Obolus ( Wesionia ) ella 4 has been found at 55 different localities, 
yet only three are referred to the Lower Cambrian and they 
are all referable to the “Pioche” or Albertella faunas. Acrothele 
collenP has been found only in the Stephen formation, in the 
beds to which the Albertella fauna was referred in British Colum- 
bia, and in the upper part of the shale which carries the Albertella 
Walcott: Mon. U. S. Geol. Survey, vol. 51, 1912, pp. 363-364. 
2 Idem, p. 357. 
3 Idcm, p. 408. 
4 Idem, pp. 457—158. 
‘Idem, pp. 641-642. 
