A HISTORY 



OF THE 



BRITISH 



FRESHWATER ALG^, 



INCLUDING DESCRIPTIONS OF 



THE DESMIDEJ; AND DIATOMACE^. 



WITH 



UPWARDS OF ONE HUNDRED PLATES, 



ILLUSTRATING THE VARIOUS SPECIES. 

 BY 



ARTHUE HILL HASSALL, 



FELLOW OF THE LINN^AN SOCIETV ; 



CEMBEIl OF THE ROVAL COLLEGE OF SURGEONS, LONDON, AND OF THE LONDON 



BOTANICAL SOCIETV ; AND CORRESPONDING MEMBER OF THE DUBLIN 



NATURAL HISTORY SOCIETY. 



IN TWO A^OLUMES. 



VOL. I. 



LONDON: 



S. HIGHLEY, 32. FLEET STREET; 



AND H. BAILLIERE, 219. REGENT STREET. 



EDINBURGH: SUTHERLAND & KNOX, 58. PRINCE'S STREET. 



PARIS : J. B. BAILLIERE. LEIPSIG t T. O. AVEIGEL. 



1845. 



