Page:Transactions of the Natural History Society of Northumberland, Durham, and Newcastle-upon-Tyne (1867).djvu/283

5. P. crispus Potamogeton crispus, L. Native. British type. Area C, N, D. Range 1.

Frequent in ditches and slow streams, ascending to the Till at Wooler, in Coquetdale to Rothbury, in Weardale to Stanhope, 200 yards.

6. P. perfoliatus Potamogeton perfoliatus, L. Native. British type. Area C, N, D. Range 1.

Frequent in slow streams, ascending to Crag Lough, 200 yards.

7. P. lucens Potamogeton lucens, L. Native. English type. Area C, N, D. Range 1.

Plentiful in the Tweed, especially about the Union Bridge (Dr. Johnston). In the Aln and ponds near Alnwick (R. Embleton). In Tynedale in Crag Lake, 200 yards, the lake at Dudley Shiels, the mill-race at Hexham, and Prestwick Carr (F. R !). Ponds near Darlington, and in the Skerne (W. Backhouse. F!).

8. P. praelongus Potamogeton praelongus, Wulf. Native. Scottish type. Area C. Range 1.

Mentioned in the Transactions of the Berwick Club for 1854 as having been gathered in the Tweed near the Union Bridge.

9. P. heterophyllus Potamogeton heterophyllus, Sieb. Native. British type. Area N, D. Range 1.

In Tynedale in Haltwhistle Burn below Walltown (W. H. Brown!). Prestwick Carr (F. R!). Pools near the Wescrow Burn in Waskerley Park (F.).

10. P. rufescens Potamogeton rufescens, Schrad. Native. British type. Area C, N, D. Range 1, 2.

Ponds on Alnwick Moor (J. Davidson. F!). Swinhoe Lough, and in the pond below Kyloe Crags (R. Embleton). Crag Lough and Greenley Lough (R!). In the Weel with Ranunculus peltatus Ranunculus peltatus at an elevation of 500 yards (B.).