SOME NOVA SCOTIA N AQUATIC FUNGI. MOORE. 



231 



most Achlyas 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 Aj^lave.^. Under 

 such circumstances the germ 

 tubes shew^ a rapid growth of 

 from 30-40/U. 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*. Cultures of the species were 

 made for some months in water containing a few living sphagnum 

 plants, and under these conditions the zoospores invariablj' 

 followed the normal course. At will, tlie A'phines condition 

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

 watcii glass, but it soon disappeared upon return to its original 

 habitat. When oogonia ai-e produced in a chain or series the 

 antheridial branches attaclied to the distal members of the series 

 take their origin from the walls of the oogonia ne.\t below*, as 

 in the case of Scqjrolegnia androgyna Archer^, {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 15--25. In old 



