8o TJic Afiicncan Geologist. February, w^>^ 
distribution of animals in Cambrian and ( )rdovician times. 
Mr. Matthew, *in an address on the ""Ditfusion and Sequence of 
the Cambrian Faunas," comments upon the deep-sea charac- 
ter of the various graptoUtic faunas, as expressed in the com- 
position of graptolites, Triarthrus, deep-water sponges, and 
brachiopods. The graptolitic faunas are enumerated, the last 
being that of the Utica slate. In reference to this is related 
that after the irruption of the Arenig fauna and the following" 
restoration to more genial conditions in the beginning of the 
Trenton period, a new fauna invaded the territory held in the 
east by the Trenton fauna, that of the Utica slate. This fauna- 
succeeded in extending itself further west than its predeces- 
sors of the Atlantic coast containing graptolites. Besides oc- 
cupying the St. Lawrence valley, it was spread westward 
across the provinces of Quebec and Ontario, and southward 
through New York and Pennsylvania. In contrasting the 
slow migration of shallow water forms with that of the inhab- 
itants of the deeper and colder sea, the following statement is 
made: "No sooner do the latter appear in Europe than al- 
most simultaneously we find them (or species closely related 
to them) on the Atlantic coast of the new world." This im- 
plies the assumption of a migration of the deep-water forms, 
characteristic of the Utica shale, from Europe to North 
America. 
The same idea is still farther developed in another ad- 
dress,f in which Mr. Matthew contrasts the faunas of the 
warm and shallow water with those of the colder and deeper 
water, and concludes that the coralline limestones represent 
the preponderance of warm shallow water, the graptolitic 
mud deposits representing the deeper and colder parts of the 
ocean. Applying this principle to the succession of calcareous 
terranes, containing corals and large mollusks, and of the dif- 
ferent graptolitic shaly terranes of the North American Cam- 
brian and Ordovician, Mr. Matthew concludes that this suc- 
cession was caused by alternating incursions of deep cold 
water faunas from Europe, and of warm shallow water faunas 
from the American Mediterranean sea. Two sketch maps 
*Published in: Trans. Roy. Soc. Canada, Vol. X, Sec. IV, 1892, p. 3. 
tThe Climate of Acadia in the Earliest Times. Annual Address. 
Bull. Nat. Hist. Soc. New Brunswick, No. XI,. 1893, p. 3. 
