25. ONAGRACE^. 375 



that their intermediate forms might be assigned to either of 

 them with about equal appearance of correctness. On 

 the other side, mountain examples of E. tetragonum oc- 

 casionally pass for the present species. 



875. QCnothera biennis, Lin 



11. 



Area (1 2 3 4 5 6 7 * 9 10 11 * 13). 



Alien. Introduced from America, and now to some de- 

 gree established on the coasts, sandy wastes, and culti- 

 vated ground in this country ; so that it finds place in 

 various local lists, as well as in the more general Floras 

 of Britain. 



376. ISNARDiA PALUSTRis, Linn. 



Area * 2. 



South and North limits in Hants and Sussex. 



Estimate of provinces 1. Estimate of counties 2. 



Latitude 50 — 51. Local or English type of distribution. 



Agrarian region. Inferagrarian zone. 



Descends ? Ascends ? (50 yards, more or less.) 



Range of mean annual temperature, probably, about 50. 



Native. Paludal or Lacustral. Three localities for this 

 very local plant have been recorded, two of them in 

 Hampshire, one in Sussex. Being a species of incon- 

 spicuous size and flowers, it may readily have been over- 

 looked in other spots. 



