148 POTAMOQETONACEJS. 



canal near Lough Neagh ; Cyh. Mib. Bog meadows ; T.H.C. 

 Mr. Templeton found this species growing in M 'Clean's fields, 

 where Bedford Street now stands. 



Order LXVIII. POTAMOGETOHrACEJE. 



POTAMOGETON' Limi. Pondweed. 



1. P. natans linn. 



Still water of ditches, lakes, and reservoirs — very common. Fl. mid. 

 June till mid. Aug. 



Var. a P. ovALiFORMis Fieber. 



Drains by Portmore Lake, Co. Antrim ; S.A.S. The foliage of this 

 form somewhat resembles that of P. plantagineus. 



2. P. polyg-onifoUus Pourr. 



Shallow pools, and ditches — common, especially on bogs and heaths. 

 Fl. mid. June till mid. Aug. Rises to over 1200 feet on the mountains. 



3. P. rufescens Schrad. 



Slow running streams, rarely in water entirely still — frequent. Fl. 

 mid. June till end of July. 



Down — Newry canal, and drains by Magherascouse Lake ; S.A.S. 

 Antrim — Malone; Templeton, 1809. Lagan canal near Belfast; Flor. 

 Ulst. Ballymena ; Cyh. Bib. Loughmourne ; S.A.S. In 

 the Sixmilewater at Templepatrick ; T.H.C. Grlendun ; Rev. 

 S. A. Brenan. 

 Derry — West side of Enagh Lough ; D.M. In the river Roe ; Ctjb. Hib, 

 More frequent than appears from the above, but there is a lack of notes 

 referring to definite localities. 



4. P. heterophyllus Schreb. 



Rivers, and lakes — rare. Fl. mid. June till mid. Aug. 

 Down — In the river near Ballynahinch ; Templeton, 1813. 

 Antrim — Lagan canal above Lisbum, Sixmilewater from Ballyclare to 

 Dunadry, Lough Neagh north of Toome, and in Loughmourne 

 above Carrickfergus ; S.A.S. 

 Now lost at Ballyclare through fouling of the water, and in Lough- 

 mourne by conversion of the lake into a reservoir. 

 Derry — Abundant in the Bann near Kilrea ; D.M. 



