POTAMOGETONACEM. 149 



Var. m P. pseudo-nitens Bennett. 

 Very rare. Found in the large lake at Ushet in the Island of Eathlin ; 

 S.A.S. 



5. P. nltens Weber. 



In lakes — very rare. Fl. June and Juiy. 

 Down — North side of Lough Aghery, plentiful in one spot where the 



bottom is peaty, but fruit stems scarce ; S.A.S., July, 1887. 

 Antrim — ''There is a specimen of this species among the plants collected 

 by D.M. many years ago in Antrim. It was probably gathered 

 in Lough Neagh " ; Cyb. Hibernica. 

 It is only since going to press that we have any information as to this 

 species beyond the doubtful note above quoted. 



6. P. lucens Linn. 



In rather deep water of lakes, streams, and reservoirs— frequent. Fl. 

 mid. June till mid. Aug. 

 Down — Newry canal in many places ; S.A.S. 



Antrim— Lagan canal above the second lock; Templeton, 1801 (still found 

 at various points in the Lagan). Loughmoume (now lost), 

 and plentiful in Lough Neagh ; S.A.S. 

 Derry— Lough Beg, and common in many parts of the county; D.M. 

 In the Bann at Toomebridge ; JF. Thompson. Streams on 

 west side of Lough Neagh ; Flor. Ulst. In the lough from 

 Toome to Ballyronan ; S.A.S. 

 Var. P. BOREALis Tiselius. 

 In Loughmome above Carrickfergus, but now lost in consequence of 

 operations by the "Water Commissioners. 



7. P. Zlzli Roth. 



Lakes, and slow streams — rare. Fl. July and Aug. 

 Antrim — Loughmoume ; S.A.S. East side of Lough Beg near Toome ; 



T.H.C. 

 Derry— "West side of Lough Beg; T.H.C. In the Bann above Cole- 

 raine ; S.A.S. 

 First found in Ireland by S.A.S. in Fermanagh. 



8. P. praelongus Wulfen. 



Lakes, and canals — rare. Fl. June and July. 



Antrim — Loughmoume ; Flor. Belf. Ditches by the Lagan between 



first and second lock of the canal ; Flor. Ulst. In Lough 



Neagh ; Cyb. Hib. In the canal at several points between 



Belfast and Lisburn, and plentiful in the large lake (Ushet) 



