256 Canadian Record of Science. 
Protolenus (P. elegans) is first found in the middle of the 
shales of 2 (see section) but it becomes more abundant in 
the upper third of this number of Band 6, and is accom- 
panied by an ostracod, Beyrichona tinea, which also 
occurs in the next two numbers, 3 and 4. Near the top of 
the “2” shales, Protolenus is accompanied by an Ellipsoce- 
phalus, not, however, the species of the sandstone number 
3, but a larger species HL. grandis, (M.S.) In the sandstones 
the Protolenus has disappeared and these beds in the lower 
part have yielded no trilobite. But about the middle of the 
sandstones Hilipsocephalus galeatus comes in and toward 
the top there is a somewhat diversified fauna of trilobites 
including H. galeatus, H. articephalus, and Protolenus 
paradoxoides. On account of the abundance of the Ellipso- 
cepli in the sandstones of 3, this member may be regarded 
as the zone of Ellipsocephali.’ 
And as Protolenus elegans is the characteristic species of | 
the shales which constitute 2, these shales are to be regarded | 
as the zone of Protolenus—-a new horison between the 
two sandstone numbers 1 and 3, whose faunas have already . 
been to some extent known. 
In conclusion a synopsis may here be introduced, suggest- 
ive of the bearing of these discoveries on the probable chro- 
nological relation of several species of the genus Olenellus, 
as inferred from their companion species (of which repre- 
sentative species occur in the subfaunas of the Band 2.). 
Acadian Species. Eastern Species Olenelli. 
Band 63. —‘Ellipsocephalus § Ellipsocephalus { Holmia. 
galeatus. Nordenskjoldi. Kjerulfi. 
Band b 2. Protolenus Protolenus { Holmia. 
elegans. Howleyi. Broggeri. 
: Mesonacis. 
BHINOL 1 E Y 1" sicko 
1 Band b hag already been spoken of as the zone of Agraulos [=Ellipsocephalus] 
articephalus. See Trans. Roy. Soc. Can. vol. viii-iv. p. 129. 
