34 81. FLUVIALES. 



Latitude 50 — 60. British type of distribution. 



Agrarian region. Inferagrarian — Suj)eragrarian zones. 



Descends to the coast level, in the Peninsula. 



A-Scends to 100 or 200 yards, in England. 



Range of mean annual temperature 52 — 46. 



Native. Lacustral. Again we have two or more alleged 

 species combined as one ; but in this instance by almost 

 general consent of British authors. Judging by the re- 

 corded localities, including those communicated to me in 

 manuscript notes, the ZannichelHa occurs in nearly aU 

 the English counties, although known only in seven or 

 eight of the Scottish counties. Northward from the vici- 

 nities of Edinbui'gh and Glasgow, Sutherland and Orkney 

 are the only recorded counties, and both on the authority 

 of Mr. J. T. Syme, who has already done much towards 

 increasing our knowledge of the local botany of Britain, 

 and from whom botanical science is likely to receive 

 much more aid hereafter. 



1137, c. Zannichellia polycaepa, Nolte. 



Area [?] 



Incognit. Given by Dr. Walker Arnott in the British 

 Flora, sixth edition, but without the indication of any lo- 

 cality for it. Hence it was taken into the third edition 

 of the ' London Catalogue of British Plants.' On the 

 other hand, in the Manual of British Botany, thii'd edi- 

 tion, Mr. Babington writes, that the Z. polycarpa of 

 Nolte " has not been found in Britain." 



