

64 BOTAXICAL GAZETTE [july 



immersa. Sporangia perdurantia intra cellulas plantarum viventium e 

 mycelio filiformi perforatas formata, copulatione cellularum similium orta. 

 Cellulae alterius protoplasma in alteram effunditur, haec vero crescit et mem- 

 brana crassa cincta in sporangium perdurans mutatur. 



The studies of the alfalfa crown-gall organism by Magnus did 

 not establish the characters cited by Saccardo. The descriptions 

 of the genus as given by Engler and Prantl (12) and by Migula 

 (24) also include characters that Magnus apparently did not verify. 



The writer has failed to observe, in the organism studied, 

 the characters ascribed to the genus Urophlyctis. In view of the 

 incompleteness of the results, no change of classification is sug- 

 gested at the present time. It seems highly desirable, however, 

 that careful investigations be made of the various organisms referred 

 to this genus. Possibly it may prove necessary to discard some 

 of the previously used diagnostic characters and to redescribe 

 the genus on the basis of fuller observations. The relationships of 

 the Chytridiaceae are in an unsettled state. There have been 

 many suggestions in the literature that would lead one to ques- 

 tion whether or not this family finds its proper place 



amon 



Phycomycetes. The studies upon which classification has 

 based in many cases have been very superficial, and few < 

 have been made to follow out complete life histories. Ca 



in 



ch an amoeboid or plasmodial stage has been noted, with the 

 ence of anything resembling mycelium excepting naked threads 

 protoplasm, furnish reason to suspect that the family is more 

 ely related to the Myxomycetes than to the Phycomycetes. 



Summary 



i. The resting spores, placed in water cultures, develop into 



sporanges. 



Within these sporansres are formed motile 



many small ones are formed 



in the same 



may 



large zoospore. Only one remains permanently attached. There 

 is some evidence that this attachment is related to a sexual fusion. 



movement 



ttachment 





