Notes on Devonian Plants from Scotland. 13 
Fig. 3. Branching stem of PaRKA DECIPIENS ( MINOR, 
showing at the base, a stem of PstLopHyTon and a frag- 
ment of Parka lying across it. Natural size. 
Plate IT. 
Fig. 1. Plant of ZosTEROPHYLLUM MYRETONIANUM. Na- 
tural size. 
Fig. 2. Fertile stem of Z. MyRETONIANUM (?) showing 
immature fruit bodies. Natural size. 
Fig. 3. Separate and mature fruit bodies of Z. MyRETo- 
NIANUM (?). Natural size. 
SomE LAKE AND RIVER TEMPERATURES. 
By A. T. Drummonp. 
In Nature and this journal, | have already drawn atten- 
tion to the fact that the Georgian Bay is, in its main ex- 
panse, a large body of cold water whose temperature, at its 
greater depths, is not much influenced by the heat of sum- 
mer, whilst, on the other hand, the Central and Southern 
Basins of Lake Huron, although also receiving surplus 
waters from Lake Superior, stand in the line of inflow of 
the warmer waters from Lake Michigan and of their ulti- 
mate exit by way of the River St. Clair to the lower lakes, 
and are consequently somewhat warmer basins. 
Staff-Commander Boulton, R N., has been good enough to 
communicate some further records of temperature made 
during the season of 1890 in the Georgian Bay and the 
channel north of the Manitoulin Islands. These, taken in 
connection with his former results, justify certain conclu- 
sions to which reference will be made in this paper.’ 
PARRY SOUND. 
In the course of his soundings during 1890 in the deep 
and wide but land-locked harbor of Parry Sound, on the 
eastern coast of the Georgian Bay, with its fringe of islands 
1 The readings in this paper are all from Fahrenheit’s scale. 
wo 
