272 H. MARSHALL WARD. 



Observations on Saprolegniae. 



By 



H. Harsliall TFard, B.A., 



Berkeley Fellow of Owens College, Victoria University. 



With Plate XXII. 



The Saprolegnice are a family of Fungi characterised 

 especially by their aquatic habits and correlated delicate struc- 

 ture ; they are for the most part Saprophytes^ flourishing on 

 the decaying bodies of animals or plants in water, though 

 several are now known as parasites on living members of both 

 kingdoms, in which they cause profound destructive changes, 

 sometimes ending in the death of the host. 



To the latter parasitic forms belong Saprolegnia de 

 Baryi and S. Schachtii, found in the cells of Algfe and 

 Hepaticse respectively, according to Walz^ and Frank,- and 

 especially the Saprolegnia of the " salmon disease," according 

 to Professor Huxley.^ 



Generally described, the Saprolegniae consist of a thallus,* 

 bearing reproductive organs of two kinds — zoosporangia 

 and oogonia, with or without accompanying antheridia. 

 The thallus consists of long, branched, tubular hyphae, of 

 which the main portions are free or ^' extramatrical ;"^ shorter, 



1 'Bot. Zeitg.,' 1870, p. 537. 



2 ' Kraiikheiten der Pfl./ erste Hiilfte, p. 383. 



3 This Journal, 1882, p. 311. 



■• It seems almost necessary to preserve the general name Thallus Iiere, as 

 De Bary lias done in liis recent memoirs, although the Saprolegnia; are 

 accepted as Pungi, chiefly on pliysiological grounds. 



^ De Bary, 'Beitnige zur Morph. u. Phys. der Pilze,' 4th scr., 1881. This 



