52 Rhodora [MARCH 
In the summer of 1918, while I was a member of the party engaged 
in a survey of Miramichi Bay and the Miramichi River, New Bruns- 
wick, under the auspices of the Biological Board of Canada, I had an 
opportunity to make an ecological study of the algae of this region. 
The survey covered the bay and the river as far as the head of the tide 
on the Nor-west Branch of the Miramichi and data on the tempera- 
ture and salinity of the water were secured at numerous stations 
throughout this range, the observations being made weekly during 
June, July, August, September and early October at some stations 
and fortnightly at the stations furthest up the river. For copies of 
the records of salinity and temperature thus obtained I am indebted 
to Dr. A. G. Hunstman, Director of the Atlantic Biological Station 
and chief of the party on the Miramichi. 
One of the most abundant algae of this estuary is Enteromorpha 
crinita. This species in its typical form is a branched tubular green 
alga with short monosiphonous tips at the end of the branches. A 
study of this species soon revealed the fact that it varied greatly in 
form in different parts of the estuary and further investigation showed 
that this variation was correlated with the salinity of the water. 
At Station 76 in Miramichi Bay the salinity at the surface varied 
from 7.38 to 24.40 per mille, giving an average of 19.12 per mille, and 
at 12 metres the range of salinity was from 19.58 to 27.36, averaging 
24.64. Since the specimens of Enteromorpha crinita examined were 
growing in the littoral zone and were in surface water when the tide 
was nearly low, and in deeper water when the tide was at full flood 
we can take a single salinity—arrived at by adding together the aver- 
age surface salinity and the average salinity at 12 m and taking the 
mean, which in this case is 21.88—as representing the salinity of this 
habitat. At this station the plants were much-branched and had 
short monosiphonous tips. 
At Station 81, at the mouth of the river, the salinity data was as 
follows: 
Surface 1.41-19.33. Average 10.08. 
At 12 m. 16.04-22.77. Average 21.34. 
Average salinity 15.71. 
Here the plants were similar in form to those of Station 76. 
At Station 82, some three miles up from the mouth of the river, the 
data was as follows: 
