Modea.'] HTDEOCHAEIDE^. 333 



scarce, and said to be decreasing rapidly liere in 1896; N. G. — 

 X. Trasna Island, &o., Lough Erne, but not plentiful and decreas- 

 ing fast: Barrington 1884. — XI. Abundant in tbe river Erne 

 between Ballysbannon and Belleek : Sort z88j y. — XII. In a pond 

 at Wariiigstown, Co. Down, about 1836 {John New) : Phytol. 

 18^4. Known near Lisburn for more tban twenty years : Flor. 

 Vht. 1864. Lagan canal ; Lougb Ifeagb ; Portmore Lake ; Bally- 

 nabincb Lake ; Newry canal, &c. ; abundant in tbe Ifortb-East : 

 Flor. JSf.-K 



Rare or absent in tbe extreme Nortb and Soutb-"West. 



A North- American water- weed introduced iato Ireland about 

 1836, and interesting, not only for its remarkably rapid increase, 

 but also for the tendency to an equally rapid decrease which it has 

 shown of late years. The rather full details of its distribution 

 given here wiU enable future observers to judge whether this 

 tendency be permanent. 



What seems to be the earliest appearance of the plant in Ireland 

 (and in the British Isles) is thus recorded in a note by Mr. John 

 New, gardener, communicated to the Bot. Soc. of Edinburgh in 

 Eebry., 1854: — " About eighteen years ago the pond at "Warings- 

 town was cleared of over-hanging trees, when the Anaohwris was 

 immediately observed after the planting of some aquatics, making 

 it necessary several times during the summer to clear it out. It is 

 not known whether it existed in the pond previously to the above 

 date or was introduced with the aquatics at that time " : Phytol. 

 i8s4, P- 88. It is, however, suggested by the authors of the Flora 

 of North-East Ireland that this plant was first introduced with 

 squared timber imported from Canada to Belfast. 



HTDEOCHAEIS Linn. 

 1. H. Morsus-ranse Linn. — Frog-hit. 



Districts -. V. VI. YII. Till. IX. X. — XH. 



Lat. 53^°-54J°. Middle and North, chiefly. Type, English. 



Lowland. Bog-holes, ditches, and .slow streams; local. Fl. 

 July-August, 



V. Common in the bog of Curragha, Dublin : Wade Rwr. 1804. 

 In bog-pits near Babuddery {Br. Scott) : MacL Bar. Sparingly in 

 Curragha bog ; and in the Broadmeadow Water ; and abundant in 

 the Bog of the Eing near Bakothery, Dublia : iV. C. i8gj. 



