no DR. J. W, HF.SLOP HARBISON ON 



Caltha palustris a Rubus spp o 



Lychnis Floscuculi a Fraxinus excelsior r 



L. dioica a Salix caprea o 



Epilobium hirsutum la S. triandra o 



Geranium pratense /" S. alba o 



Angelica sylvestris /" Populus tremula o 



Valeriana sambucifolia f P. nigra p 



Cnicus palustris o Phalaris arundinacea f 



Tanacetum vulgare la Carex vulpina la 



Pulicaria dysenterica la Juncus spp a 



Mentha spp la Equisetum palustre la 



Vicia cracca a and various intruding 



Lathyrus pratensis f Graminaceae a 



Billingham Beck, the Mill Race and its Evibankment. 



Owing to the vital importance of keeping the beck con- 

 stantly cleared to secure a steady flow in such a low-lying 

 district, it is periodically cleaned out. As a natural result, 

 although many plants occur in isolated clumps, they are never 

 associated except perhaps when Nynnphaea liitea abounds ; with 

 it there flourish quantities of Alisma plaiitago-aqi/atica, Scirptts 

 lacustris, Spa7-ganium ramosum and the like. 



On the banks only Salix triandra and Sy?npliytn?n officinale 

 call for comment. 



As the bottoms lie so low and are so regular, and since 

 the Mill Race follows the 25 foot contour line, the embank- 

 ment holding it rises very sharply from the meadows and 

 would, therefore, hold no promise of a further marsh. Such, 

 however, owing to the water containing powers of its irregular 

 clayey slopes exists there. 



Both the race and the slope being of ancient origin, and the 

 former long since disused, they are colonised by suitable 

 plants. Nor are these exactly the same as those listed for the 

 adjoining marshy ground ; in the Mill Race, Glyceria aqtiatica 

 plays the dominant part although, save for Mentha arvensis 

 (with hybrids) and Veronica anagallis, its fellow colonists are 

 the same as those studied in the lodes and the heck. In 

 addition, Hypnvfn 7-iparinni is locally common. 



