476 Canadian Record of Science. 
tion may now be given to these forms, for they do not by 
their presence exclude the Ceratopyge or Tremadoc beds 
from the Cambrian. Nevertheless, under the classification 
proposed by Messrs. Salter and Hicks some twenty years 
ago, the Cambrian is divided into two great divisions only. 
The purpose of the present article is to review some of the 
evidence touching the faunas and the sedimentation of this 
system, and to compare the proposed division with that pre- 
sented by Dr. Hicks." 
Late discoveries in America and Hurope, and especially 
the enlargement of the fauna with Olenellus and the dis- 
covery, or rather the determination of its proper place in 
the Cambrian succession, has led to this proposal for a new 
allotment of the parts of the Cambrian system. j 
If the object in view were merely the arrangement of the 
members of this system which may occur in any particular 
country, the sedimentation, or division into series, in that 
country could be utilized for the purpose, but as the object 
is a classification that will apply generally, other criteria 
must be sought. Among those which have been used are 
the succession of the several faunas and the relationship of 
the genera in each; and the comparative bulk of measures 
n the several parts of the system. These form the basis of 
the following remarks, 
The Cambrian rocks as originally described by Prof 
Sedgwick no doubt contained the Ordovician or Lower 
Silurian as well as the strata to which the name has since 
been restricted. These (the Lingula flags, etc.) were also 
claimed by Sir R. Murchison as a part of his Silurian sys- 
tem. In later times the conflicting claims of these dis- 
coverers have been compromised by assigning to each his 
own special domain, and erecting the disputed territory 
into a separate system, the Ordovician. 
The development of the Cambrian system from its origi- 
nal basis in the Lingula flags, etc., received a great 
impulse from the discoveries of Dr. Henry Hicks and the 
late Mr. J. W. Salter, in Wales; and especially in the find- 
* Pop. Sci. Review, N.S. Vol. 5. 
