A HISTORY 



OP THE 



BRITISH 



FRESHWATER AL(LE, 



INCLUDING DESCRIPTIONS OF 



THE DESMIDEJ; AND DIATOMACEJ. 



ILLUSTRATING THE VARIOUS SPECIES. 

 BY 



ARTHUR HILL HASSALL, M,D, LOND, 



AUTHOR OF 



THE "MICROSCOPIC ANATOMY or THE HUMAN BODY;" 



LICENTIATE OF THE ROYAL COLLEGE OF PHYSICIANS OF LONDON; 



FELLOW OF THE LINKSAN SOCIETY ; 



MEMBER OF THE ROYAL COLLEGE OF SURGEONS OF ENGLAND ; 

 ONE OF THE COUNCIL OF THE EPIDEMIOLOGICAL SOCIETY, 



ALSO OF THE BOTANICAL SOCIETY OF LONDON ; 



CORRESPONDING MEMBER OF THE DUBLIN NATURAL HISTORY SOCIETY J 



PHYSICIAN TO THE UNITED KINGDOM LIFE ASSURANCE 



COMPANY. 



IN TWO VOLUMES. 



VOL. I. 



LONDON: 

 TAYLOR, WALTON, AND MABERLY, 



UPPER GOWBR STREET ; AND IVY LANE, PATERNOSTER ROW. 



1852. 



