186 REPORT OF THE AMERICAN COMMITTEE. 
sition to Bischof's statement that graphite is not found in the 
unstratified crystalline rocks, it is maintained that it is " almost 
exclusively confined to granite, gneiss, quartz, mica-slate, crys- 
talline limestone, and the older slates." The claim, therefore, 
that graphite is a proof of organic life is unfounded ; no traces 
of new life having been found in the graphite of the Azoic 
series. Carbonate of lime does not imply the intervention of 
organized beings, as its formation is constantly going on without 
them. Iron ores also do not prove the presence of organic 
life, as iron is one of the commonest components of eruptive 
rocks. To sulphur the same argument applies, and to apatite 
as proving by phosphorus animal life. Finally he demon- 
strates that the rocks called by Foster and Whitney "Azoic" 
are in fact non-fossil iferous. 2d. As to the grounds for dividing 
the Pre-Cambrian into two or more classes, the division of the 
Laurentiau from the Huronian by the appearance of fossils 
in the latter, was abandoned by the Canadian Survey. The 
Aspidella as a fossil is dismissed as a concretion intersected by 
small irregular cracks. The Arenicolites spiralis is, on Dr. 
Wadsworth's examination, rejected. 
The division of the Laurentian from the Huronian is attributed 
to Logan's confounding the basaltic volcanic rocks interbedded 
with the Potsdam sandstone of Keweenaw Point with the basic 
or greenstone portion of the Azoic of Foster and Whitney as 
developed north of Lake Huron. In regard to the accepted 
succession and unconformability, the Huronian resting on the 
upturned edges of the Laurentian, it is stated that of the seven 
cases in the Canada Survey, when the contact was observed, in 
five they passed imperceptibly into each other; in a sixth they 
show mutually intrusive relations, and in the seventh the 
Huronian abuts against and runs under the Laurentian. 
The conclusion of this laboriously prepared work is that there 
is undoubtedly a series of rocks beneath the lowest fossiliferous 
horizon ; that this series has thus far proved unfossil iferous ; 
that it has been called Azoic by Foster and Whitney before 
Logan applied the terms Laurentian and Huronian to his former 
"metamorphic"; that no division has been found which holds 
good over an extended region ; and that hence the rocks in 
question should be called the " Azoic," and should not at present 
be divided. It appears to your reporter that the main question 
