Is the Primordeal the Most Ancient Fauna? 349 
trilobites were inclined to pass. Tullberg had shown this 
for the Agnosti of Scandinavia. 
The author shows that the earlier forms of Paradoxides 
were small and the gigantic form P. Regina was one of the 
later. These large species perished suddenly without leaving 
any successors. The same rule holds for Asaphus and II- 
lanus and large species of other genera. 
“The preceding study of the characters peculiar to the 
trilobites of the Cambrian has led us to the conclusion 
that these present sure indications of an evolution anterior 
to the epoch in which they lived. This leads us to think 
that there must have lived prior to the fauna called primor- 
deal, one which may have contained the ancestral types of 
the most ancient one that we actually know.” 
Dr. Bergeron supports this view of the source of the most 
ancient forms of animals known by an outline of the opinions 
now held in regard to the metamorphism of the older sedi- 
ments, by which the proofs that may have existed in the 
pre-Cambrian rocks of the life of that earlier epoch have 
been destroyed. 
This article by Dr. Bergeron, published in the ‘‘ Revue 
Générale des Sciences, Paris, 1892,” is an excellent review 
of the evidence on this subject as based on the latest dis- 
coveries in geology. 
RADIOLARIAN REMAINS IN THE Azotc Rocks oF Brirrany. 
Dr. Chas. Barrois helps to solve the above question of his 
countryman (Is the fauna called Primordeal the most an- 
cient fauna?) by proclaiming the discovery of Radiolarian 
remains in the Azoic rocks of Brittany. These he dis- 
covered in a graphitic quartzite which constitutes an in- 
tegral part of the granulitic gneiss of that part of France. 
The beds have been traced through Vannes and several 
neighboring towns, where they are less affected by granu- 
litic intrusions, and become a carbonaceous quartzite and 
shale, and underlie the system called the schists of St. Léo. 
These schists are considered to be pre-Cambrian, and would 
correspond to the Huronian system of Canada, 
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