1898.] Swan. — 7,^^ Geyius Leptolegnia- 37 



the sexual fruit preceded zoospore production, to be followed 

 by the unusual chlamydospores which I have described, needs 

 a more thorough study, especially as regards the protoplasmic 

 changes which take place during their development. 



I am indebted to my friend, Prof Hartog, of Queen's College, 

 Cork, for literature and assistance in identification, and tender 

 him my best thanks. Prof J. K. Humphrey's monograph on 

 the " Saprolegniacese of the United States," 1893, has been of 

 great service to me, as it contains, in a condensed form, most of 

 the current literature on the subject, and full descriptions of 

 the commoner species. 



Description of Pirate i. 



The illustrations were photographed from life, and are magnified ^ 

 in all cases. 



Fig. I. Leptolegnia caudata, De Bary, bearing oospores. 



Fig. 2. L. caiidafa, old oospores at rest. 



Fig. 3. Leptolegnia bandoniensis. Emptied zoosporangia, showing beaks 

 with fresh protoplasm moving upward in the lower example. 



Fig. 4. L. bandoniensis. Non-sexual zoospores of varying shape, im- 

 prisoned in their sporangium. 



Fig. 5. L. bandoniensis. Encysted zoospores fifteen minutes after their 

 liberation, surrounded by empty zoosporangia. 



Fig. 6. L. bandoniensis. Sexual oospores, enclosed in their globular 

 oogonia. 



Fig. 7. Z. bandoniensis. Empty germinated chlamydospores, with their 

 contained filaments and sporangia. 



Bandon, Co. Cork. 



A3 



