114 DR. J. W. HRSLOr HARTJSON ON 



decide that the landward Glyceria and the succeeding plants 

 are to be regarded as a unit and that unit a member of the 

 Marsh as opposed to the Aquatic Formation, in spite of its 

 betraying transitional characters. We are thus reduced to the 

 consideration of three zones. 



Of these a submerged leaf association occupies that 

 furthest from tlie shore just when the Fleet deepens abruptly. 

 This association contains only two plants : — 



Wyriophylluni spicatum . ..... d Potamogeton lucens o 



Just within this, on the limits of the ledge, we have a narrow 

 band of Reedswamp dominated by Glyceria aqiiatica and less 

 frequently by Scirpus fuaritimus. No matter which is dominant, 

 the growth is very pure and almost closed, but, at intervals, 

 outposts of Scirpus lactistris project into the deeper water. 

 Very rarely S. maritimns var. jnonostaciiys displaces the type. 

 The following are the plants found here : — 



Glyceria aquatica Id Alisma plantago-aquatica ... o 



Scirpus maritimus Id Scirpus lacustris o 



Ranunculus sceleratus /' S. var. monostachys o 



Succeeding this association, we have an open marsh com- 

 munity of strange aspect, the components of which, whilst purely 

 marsh-loving plants, are proper to widely opposed associations 

 and even formations. No sight was stranger than to see 

 Trigloc/iin palu sire s.r\d T. maritivmm rubbing shoulders with 

 each other. These anomalies give a clue to the fortuitous 

 manner in which this vegetation has assembled. The plants 

 noted there were : — 



Glyceria aquatica Id Juncus compres.sus r 



Ranunculus sceleratus /' J. maritimus vr 



R. Drouetii r J. lamprocarpus r 



Nasturtium officinale a J. glaucus la 



Cochlearia officinalis ... c (on mud) Scirpus fluitans o 



Epilobium hirsutum o S. compressus o 



E. palustre o .S. setaceus f 



Atriplex patula (!) f .S. Tabernaemontani la 



Rumex conglomeratus f Eleocharis paiustris f 



R. sanguineus f Carex vulpina f 



