![Sample our Environment & Agriculture journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5934/TOC-Subject-Sample-2021-Environment-Agriculture.jpg"})
Summary
The present paper describes the finding for the first time in the United States of Pythium dictyosporum, a seemingly rare and little known phycomycetous parasite of Spirogyra crassa Kütz., the material of which was collected October, 1926, in a small pond near Belmont, Mass.
Details of the less known phases of the morphology and development of the fungus are given, especially with respect to certain critical stages in the formation of the vesicle, the method of penetration of the zoöspore, and the structure of the mature oöspore.
A brief consideration of the lack of sexual reproduction in pure culture, the identity of the various walls of the oospore, the persistence of the fertilization tube, as well as a slightly emended technical description of the fungus, are included.
The writer wishes to express his appreciation for the aid and criticism given him by Professor W. H. Weston, Jr., under whose guidance the work reported in this paper was done.