ARTICLE Y. 



THE SAPROLEGNIACE^ OF THE UNITED STATES, WITH NOTES ON 



OTHER SPECIES. 



BY JAMES ELLIS HUMPHREY, SC.D. 



Read before the American Philosophical Society, November 18, 1892. 



In spite of the attention which most families of Thallophytes have received in 

 the United States during recent years, the aquatic fungi have been hardly noticed. 

 Although their resemblances to the AlgsB on one hand, and to the Fungi on the other, 

 give to their study peculiar interest, it is perhaps to this twofold aflGinity that the 

 neglect is due. Their habitat is not such as is explored by the student of fungi, and 

 the phycologist passes them by as not of his group. 



The following pages contain the results of studies of American Saprolegniacece, 

 carried on during the past two years in the intervals of other botanical work. The 

 materials on which they are based have been largely procured by myself in and 

 about Amherst, Mass. ; but I have to thank the kindness of friends and correspondents 

 in other parts of the country for considerable material illustrative of the Saprolegnia- 

 ceous flora of their respective sections. Of these, I am indebted to Dr. Ida A. 

 Keller, of Bryn Mawr College, for cultures from the neighborhood of Philadelphia, and 

 for a single one from Kentucky ; to Rev. A. B. Langlois, of St. Martinville, Louisi- 

 ana, for cultures from that vicinity ; to Prof. Gr. F. Atkinson, formerly of Auburn, 

 Alabama, and to Mr. J. M. White, of Agricultural College, Mississippi, for speci- 

 mens from those localities. I am also under especial obligations to Prof. William 

 Trelease, of the Missouri Botanic Garden, at St. Louis, who has most generously 

 placed in my hands without restriction all the preparations, notes and drawings made 

 during his too brief study of the family, carried on chiefly in eastern Massachusetts 



A. p. S. — VOL. XVII. I. 



