1891.] PUBLIC DOCUMENT — No. 33. 215 



the unfavorable conditions of winter, and germinate again 

 when circumstances favor once more. They have been 

 shown to be able to retain their vitality for a long time, 

 under certain circumstances, but it would seem that the dry 

 air of a room is fatal in a comparatively short time ; for 

 plums of the previous season, picked April 1, and kept till 

 November 1 in a dry pasteboard box, in a closet, failed 

 entirely to produce the fungus in a moist chamber, though 

 given abundant opportunity to do so. Galloway states that 

 spores of the fungus collected in July, 1886, germinated in 

 May, 1888, but does not state how they were kept mean- 

 while. 



It has often been supposed that Monilia represents simply 

 the summer spore form of some fungus whose other stages 

 may be found on other substances. With a view to getting 

 some light on this question, several cultures of the Monilia 

 spores have been made on nutrient gelatine, prepared with 

 an infusion of prunes ; and one was continued for four and 

 a half months, without, however, producing any other than 

 Monilia spores, which appeared in three days after the 

 beginning of the culture. These facts, and the abundant 

 demonstration of the ability of its vegetative threads to 

 survive the winter, apparently through the formation of 

 resting cells or Gcmmce, point to the probability that, what- 

 ever its origin, any other forms once connected with it have 

 been lost, and it is therefore fairly safe to regard it as an 

 autonomous fungus. Other points of theoretical interest 

 came up during the progress of the cultures, which will be 

 discussed in a technical journal. 



Assuming that the Monilia, which is classed among the 

 imperfect fungi, is an independent form, and that the 

 simple course of development sketched above constitutes 

 the whole of its life cycle, the problem of avoiding to a 

 large degree the losses now annually caused by it becomes 

 a comparatively simple one. While something can prob- 

 ably be done by judicious spraying with fungicides, the 

 question is largely one of orchard hygiene. If fruit 

 growers could be made to realize the power for harm which 

 lies in a few mummied fruits, they would readily under- 

 stand that the prompt removal of every one which shows a 



