NOTE ON ARCHuEOZOON. 
549 
growth was almost immediately renewed by a new set of columns, 
occupying the fresh surface of mud that covered the old ones. 
“ In the upper part of the reef in which the columns flourished 
and grew luxuriently, it is very interesting to observe the appar- 
ent effort put forward by some of these columns to overtop their 
fellows. Those that grew most vigorously would spread and 
crowd the adjoining ones, so that they were compelled to elevate 
the centres of their calcareous layers. Thus in these crowded 
columns the layers became almost (inversely) funnel-shaped, 
while in the broad ones, that had plenty of room to grow, they 
flattened out to an (inverted) saucer shape, or in some cases are 
almost entirely -flat. It is these funnel-shaped layers which, when 
they are cut across, have the' appearance of the ends of sticks of 
wood. They have thus given to unpractised observers the im- 
pression that the rock consisted of crowded masses of wood 
turned to stone. 
“ Sometimes one of these columns was quite crowded out of 
existence by its more vigorous neighbors. In other instances we 
appear to have cases where the columns bifurcated, and formed 
two columns to occupy a space otherwise vacant on the sea bottom. 
Another feature of these columns, which helped to carry out the 
deception that led those who first saw the rock to suppose that 
each column was a stick of wood, was that the silicious* (dolo- 
mitic) layers are thinner, and sometimes fail altogether at the 
centre of the column. As the spaces between the calcareous 
layers are filled with mineral matter of a darker hue than the 
calcareous substance, (and the centre of the columns is also of a 
dark color), the columns appear to have a dark centre, 
like the pith of a tree ; hence they were thought to be the trunks 
of ‘ hardwood ' or exogenous trees. 
“ This reef of calcareous columns was about one hundred 
and fifty feet deep, but its lateral extent is not known, as it is cut 
off on one side by a fault, and on the other passes beneath the 
waters of the St. John river. 
“ A peculiarity of these calcareous columns is that they are 
usually surrounded by a casing of more magnesian substance ; 
thus a space of a quarter of an inch or more may separate two 
Prof. F. D. Adams, who has examined these layers, says they are dolomitic. 
