cA4 ROYAL SOCIETY OF CANADA 
studies were made, there is evidence of slight pressure and also of very 
little decay, from which circumstances, in connection with the absence 
of a bottom at very considerable depth, it becomes reasonable to conelude 
that the formation is still in the condition of a quaking bog, and that 
the superficial structure as now found, must have been developed within 
very recent times. 
Simultaneously with the growth of the sphagnum, other forms of 
vegetation commenced to establish themselves, each in turn, as the 
conditions of the surface became adapted to their growth. Thus 
Cassandra and other ericaceous plants immediately followed the 
sphagnum, and these were succeeded by a more mixed type of flora which 
embraced coarse grasses, sedges, and even trees. But this zona! 
development was directly correlated with diminishing volumes of water 
in exact accordance with the extent to which the surface layers became 
elevated and better drained until, finally, it became possible for the 
white pine to establish itself and still further add to the improvement 
of the general environment. 
From the account thus given, it will be seen that the jhistory of 
ihe marsh from the first formation of the ponds through the agency 
of barrier beaches, to the time when the white pine forest was abruptly 
killed, has been that of a fresh water bog, and in this it is exactly 
parallelled by more recently developed bogs which may now be found 
within (the same region in all stages of development. 
It appears, however, that there were two crises in the history of 
the Brave-Boat Harbor bog, and both ,of these occurred within very 
recent times. It has been shown that in the second stratum above the 
sphagnum, there are not only the remains of a young forest of white 
pine, but the construction of the peat itself shows that there war a 
very marked change in the environment which serves as an explanation 
of the destruction of the trees. It would seem that the young forest 
of white, pine grew upon the somewhat unstable base afforded by the 
“quaking bog” shortly after emergence from the cassandra stage. 
This condition is exactly duplicated to-day by neighbouring bogs, where 
white pine trees of about the same size may be seen in direct succession 
to the cassandra. With an increasing weight of the surface mass, this 
latter was carried down to a lower level by its.own weight, and to such 
a position as to once more establish aquatic conditions. This is made 
evident by the reappearance of the remains of aquatic plants. within the 
same zone, but immediately overlying the pine stumps. It thus became 
necessary for the bog to once more, but for a brief period only, pass 
through those phases of development previously completed. Without 
the repetition of such a catastrophe, the bog continued a normal 
