108 
MUSEUM BULLETIN NO. 2. 
(the Hota) is composed without observation as to its relations 
to the upper or lower limits of that formation. Stratigraphic 
arrangements based solely on apparent stages in the development 
of the included faunas have been a source of error in the past, 
but this new subfauna, including Olenellus as it does, appears 
to represent a horizon high up in the Lower Cambrian, even 
if it may not be as young as the Olenellus canadensis fauna of 
the Mount Bosworth section to the south. If its reference 
to the Hota is correct it is separated by at least 550 feet of 
strata from the Albertella fauna which does not contain Olenellus, 
either here or in the Mount Bosworth region, where, as has been 
stated, tons of its enclosing sediment have been -worked up in 
the minutest of detail by both Mr. Walcott and the writer. 
The absence in the Mount Robson region of any fossil collec- 
tions from this 550 foot interval as well as from the 250 feet 
immediately overlying the Albertella horizon, coupled with the 
fact that in the Mount Whyte formation of the Mount Bos- 
worth section Olenellus is also absent from the beds above the 
position to which the Albertella fauna was assigned 1 , would 
appear to lend weight to the assumption that the Che tang 
limestone and that portion of the Mount Whyte formation 
down to and including the Albertella horizon are to be referred 
to the same division of the Cambrian. As the writer has inti- 
mated in the discussion of the Mount Bosworth section, page 
106, he believes the upper portion of the Mount Whyte formation 
to be Middle Cambrian in age. Mr. Walcott 2 has placed this 
formation entirely in the Lower Cambrian, but he appears to 
recognize its kinship with the Chetang, which also carries the 
Albertella fauna, by stating 3 that that fauna occurs at about 
the same horizon in both the Mount Bosworth and Mount 
Robson sections. In his table of formations in these two 
Walcott: Smithsonian Misc. Coll., vol. 53, No. 5, 1908, pp. 212-215, gives 3 faunal 
horizons above the Albertella horizon in the ’’Lower Cambrian” Mount Whyte, 
all without Olenellus, the evidence for the statement (p. 203 of the same reference) 
that that genus “occurs so generally in the Mount Whyte formation, both above 
and below the Albertella horizon” and for the writer’s discussion of the possibility 
of the recurrence of Olenellus above the Lower-Middle Cambrian boundary (page 117), 
being the presence in a different section (the Mount Stephen), though in an apparently 
similar position, of fragments assigned to Olenellus. 
2 Smithsonian Misc. Coll., vol. 53, No. 5, 1908, p. 212. Its reference to the Middle 
Cambrian in No. 1 of the same volume, page 2, being a typographical error. 
* Idem, vol. 57, No. 12, 1913, p. 338. 
