40 
fluctans of E. B., eel. iii.) is that the lower submerged leaves are nar- 
rowly linear, being from six to eighteen inches long by iV by io to £ 
broad, not rigid, like the leafless petioles of P. natans, which they 
resembled in breadth. Neither had the floating leaves the coria- 
ceous substance carried down into the petiole, as in P. natans. To 
this form I have given the name var. linearis. Mr. A. Brotherston has 
sent me from Floors, near Kelso, a specimen of a Potamogeton without 
flowers, which I think will prove to be the same as the Killarney 
plant. I hope he may be able to obtain a supply of it in flower and 
fruit for the Botanical Exchange Club. In looking over the Edin- 
burgh Herbarium I saw a fine specimen of the P. sparganifolius similar 
to the Maarn plant, with a label stating that it was gathered in Loch 
Neagh by Dr. D. Moore, of Glassnevin. In the same collection there 
were very fine specimens of P. pseudo-fluitans , with the submerged 
leaves six inches by f broad in the middle, labelled from the Leven, 
Loch Lomond.’’ — J. T. Boswell, June, 1875. 
P. nitens, Web. “A single specimen gathered by mein the Bay of 
Islands, Upper Loch of Stennis, Orkney, August, 1873.” — J. T. Bos- 
well. 
Potamogeton lucens, L., var. “ Kinghorn Loch, 1873 and 1874. In 
1873 I found a few small patches of a Potamogeton in the north-west 
corner of Kinghorn Loch, which when in the water resembled in 
colour and apparent texture a broad-leaved form of P. polygonifolius. 
On rowing to the place and gathering it, it turned out to be what I 
had never before seen, P. lucens, producing subcoriaceous floating leaves. 
They were of a bright yellowish-green colour and firm consistency, 
much of which they lose when drying. Their petioles were ex- 
tremely short in this, forming a great contrast to the floating leaves of 
natans, polygonifolius, and heterophyllus. Some of the specimens had 
the leaves broadly ovate and shortly stalked, but still of the usual 
membraneous texture and translucent appearance. Very few of the 
plants flowered, and not a single one fruited in spite of many 
diligent searches. The water in 1873 was from one to three feet deep 
where the plant grew. In 1874 Kinghorn Loch stood at a much 
lower level, and the P. lucens was left dry, as well as the P. natans, 
with which it grew intermixed. The stems had become extremely short 
and decumbent, few of them above six inches long ; the submerged 
leaves had entirely withered, from being exposed to the air, and only 
those which were furnished with an epidermis remained, forming 
small rosette-like tufts of nearly sessile leaves. No flower or frui 
was produced, so far as I could find.” — J. T. Boswell. 
ZannicTiellia polycarpa, Nolte. “ Kerbister Loch, Orphir, Orkney, 
