342 



SEXrAL EEPRODUCTION OF VEKONOSrOKA INFESTANS. 



M.O..S. l\D.h\kT.DLL. 



Fig. 5. 



Potato P^ungus and its resting-spores. Taken from the stem of one of the Chis- 

 wick Plants, (Journal of Horticulture, p. 72.) 

 A. Cells of stem. B. Mycelial threads. EE. Zoospores. GG. Anthe- 

 ridium. FF. Oogonium H. Young resting-spores; JJ. Mature resting-spores. 



■will be seen how completely P. mfestatis agrees in its sexunl repro- 

 ductions with other species of the genus in which the process is 

 known. 



By an examination of the original specimens, the Artotrogus of 

 Montague (fig. 3) was conclusively determined to be the half-mature 

 resting-spore of the Peronospora. 



In connection with the history of this investigation, it is worthy 

 of note that the resting-spores were drawn so long ago as about thirty 

 years by Mr. H. 0. Stephens, of Bristol, and one of his drawings is 

 reproduced with notes by Mr. Smith in the " Gardeners' Chronicle" 

 for October 2 (p. 433). 



