NOTE ON ARCH.EOZOON. 
551 
at Green Head. This locality is in a more southerly basin of the 
limestones of the “ Upper Series ” than that of the Green Head 
locality, and the locality where it was observed by Dr. W. D. 
Matthew. 
The latest occurrence of the fossil noted was at Black River, 
on the coast of the Bay of Fundy, eastward of St. John, and 
quite detached from any known area of Laurentian rocks. It 
occurs at the side of the road leading from Black River to 
Loch Lomond as small boulders in a conglomerate at the base of 
the red Devonian rocks of the latter place. Extending from the 
point where this occurrence was observed, for several miles to the 
westward, is a ridge of gray grits, which may be a coarser form 
of the quartzites of the “ Upper Series ” of the Laurentian area 
seen around St. John. If this ridge is of the “ Upper Series,” 
the position of the Archasozoonal limestone would be along its 
southern face, against which the Devonian rocks now rest, and 
which may therefore be supposed to cover the Laurentian lime- 
stones if present at this place. 
The resembling fossils found by Mr. Bailey Wikis, of the 
U. S. Geological Survey, in northwestern Montana, have been 
observed in a limestone of Pi e-Cambrian age, called the Siyeh 
limestone, and have been named Cryptozoon frequens. The 
excellent haff-tone reproductions of this fossil show how close 
they are in general structure to Archaeozoon Acadiense, especi- 
ally in their convex growth and in the spaces between the 
columns. The microscopic structure of Cryptozoon frequens is 
not described in the paper I have cited, and there is no further 
means of comparison with the Acadian (Canadian) fossil; but 
that Pre-Cambrian limestones in the Rocky Mountain region, 
clearly shown to be such by their relation to a well-defined 
Cambrian terrane, should contain organic structures so like the 
Archaeozoon, is an important and suggestive addition to our 
knowledge of the earliest forms of life. 
* Bull. Geol. Soc. of America, Vol. 17, pp. 4, 6, 8, 10, 11, 19, pi. 19. 
stones if presnt at ethis place. 
