98 



DR. J. W. HESr^OP HARRISON ON 



interfere. They flower before tlie latter commence to grow, 

 and Caltha ripens its seed before the spreading leaves cut off 

 the light supply. Ranunciilns Ficaria rarely, if ever, seeds, 

 but increases vegetatively in a very vigorous fashion. 



A further source of wonder to one is the marvellous manner 

 in which Oenanthe fistiilosa maintains itself. Its first leaves 

 are necessarily produced in water, and consequently are very 

 finely segmented. Before typical aerial leaves can appear, 

 the plant is completely shaded by the Phragmitis leaves ; yet 

 it flowers and ripens seed almost destitute of foliage ! 



Of the association the following 



Phragmitis vulgaris d 



Caltha palustris a 



Ranunculus Ficaria a 



Spiraea Ulmaria / 



Oenanthe tistulosa /" 



Mentha aquatica o 



Epilobium hirsutum o 



Myosotis palustris f 



Polygonum amphibiura / 



Galium palustre f 



Hippuris vulgaris la 



is the average composition : 



Rumex Hydrolapathum r 



Iris pseudacorus „ o 



Carex riparia f 



C. vesicaria o 



C. gracilis o 



C. paludosa f 



Equisetun limosum o 



Hypnum cuspidatum f 



Hypnum aduncum 



var. pseudofluitans f 



Aulacomnium palustre f 



At one station in the reed swamp, a slight elevation 

 surrounded by an intensified depression occurs; here a sub- 

 association dominated by Phalaris arit/idinacea holds posses- 

 sion. So like the association just described is it, that it tempts 

 one to classify it as a consocies rather than an association. 

 However, slight though important differences are manifested 

 and justify the latter classification. 



The following is the list of associated plants : — 



Myosotis caespitosa o 



Iris pseudacorus r 



Carex gracilis r 



Equisetum palustre f 



Hypnum cuspidatum / 



Mnium affine, var. eJatum ... la 



Phalaris arundinacea d 



Spiraea Ulmaria Id 



Caltha palustris f 



Cardamine pratense f 



Mentha aquatica / 



Myosotis palustris o 



