326 ON NAIAS GRAMINEA DEL., VAR. DELILEI MAGNUS. 
Naias was not aboriginal. All the other plants were of the 
prevailing canal character, the non-native Anacharis being as much 
at home as any of them. ae 
e temperature of the canal water is, however, artificially 
raised by the discharge of hot water from boilers and condensing 
tanks attached to the cotton-mills and other works, which are 
erected on the banks of the canal. In the declining evening of 
passing barges. Another interesting plant grows with the Chara, 
whose identity is by no means settled, and it may prove worthy o 
@ more detailed notice viz., a species of Zannichellia. 
of the canal, with Chara Braunii and Potamogeton pusillus ; it 
occurs in places where the water scarcely covers it. It would 
The Zannichellia grows in the soft mud in the shallower pam 
L so 
the fruits which are produced in mud are of a very pale yellow- 
green, on account of their imperfect exposure to the light. From — 
the dwarf, creeping, habit of the plant it seems to have an affinity — 
with the form of 4. palustris, named 4. repens Benningh. The — 
