SOME NOVA SCOTIAN AQUATIC FUNGI. MOORE. 



231 



most AMyas with regard to the 

 behaviour of the zoospores. 

 When a culture is placed in a 

 small quantity of water in a 

 watch glass all of the sporangia 



may fail to empty and the 

 zoospores germinate after the 

 manner of an Aplants. Under 

 such circumstances the germ 

 tubes shew a rapid growth of 

 from 30-40/n per hour. In other cases, where the environment 

 does not appear to be favorable to normal developement, the 

 zoospores may escape and, after the first encystment, germinate 

 without a second swarming stage, as appears to be normal 

 manner in A. aplanes Maurizio 4 . Cultures of the species were 

 made for some months in water containing a few living sphagnum 

 plants, and under these conditions the zoospores invariably 

 followed the normal course. At will, the Aplanex condition 

 could be induced by removing the culture for a few hours to a 

 watch glass, but it soon disappeared upon return to its crigina-1 

 habitat. When oogonia are produced in a chain or series the 

 .antheridial branches attached to the distal members of the series 

 take their origin from the walls of the oogonia next below, as 

 in the case of Saprolegnia androgyna Archer 5 , (Aplanes braunii 

 deBary). The number of oospores in the first formed oogonia 

 on the main filaments or large branches is generally large, 

 ranging from 8 15, and frequently from ]5 25. In old 



